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TechTool Pro 6 Tests  Tests

TechTool Pro includes options to test various hardware components, drives, and other aspects of your computer system. These include tests that run automatically at program launch as well as tests that you select to run from within the Tests category. These testing options are covered below.

Check Computer

Memory Test

Surface Scan


Volume Structures

Video Memory

File Structures


Automatic Tests

When you launch TechTool Pro, a group of five hardware tests run automatically. On completion, the test results are displayed on the gauges in the stage area at the top of the screen.


Check Computer Stage


Refresh ButtonThese tests can also be run and the gauges displayed after completion of manual testing by clicking the refresh button on the lower right side of the stage or by pressing the return or enter key. Details of the five tests follow.



USB stands for Universal Serial Bus. It is a medium speed protocol for connecting devices to a computer. USB can oper- ate at 1.5 Mbps or 12 Mbps. The USB 2.0 standard has a raw data rate at 480 Mbps, and the latest USB 3.0 standard a rate of 5 Gbps. USB is present on all recent Macintosh models. In addition, USB ports may be added via PCI cards or as USB hubs attached to existing ports. Typical USB devices include keyboards, mice, joysticks, game pads, and other low-band- width, low-cost devices. Unlike FireWire, USB controls periph- eral devices in a master/slave relationship. USB offers several benefits such as low cost, expandability, auto-configuration, hot-plugging and outstanding performance. It also provides power to the bus, enabling many peripherals to operate without the added need for an AC power adapter.

TechTool Pro checks the built-in USB bus in your computer to ensure that it is functioning. If the test passes, the speed of the USB interface is displayed in the USB gauge. If the test fails or if no USB interface is recognized, this will be indicated on the gauge. TechTool Pro cannot test the functioning of the USB ports since this would require additional hardware.


Cache is fast RAM (random-access memory) that is used to store data for CPU operations. Cache speeds up processing by storing frequently used instructions. Since the cache is built into the CPU itself, it can be accessed at a faster speed than memory attached to the standard system bus. A good analogy to the cache would be a bulletin board that holds frequently used phone numbers on Post-It™ notes. The numbers would be available on the board for quick reference. That way you would not need to take the time to look them up in the telephone book (analogous to main memory) every time they were needed.

TechTool Pro checks for the presence of cache and, if found, tests it and displays its speed on the Cache gauge. If the cache tests fail or if no cache is detected, this will be indicated on the gauge.


Every computer contains one or more CPUs (Central Processing Units). These are the "brains" of your computer. If more than one processor is present, they may reside on individual chips (such as in a dual processor G5), may exist as multiple cores on one chip (such as in an Intel Core 2 Duo iMac), or both (such as in a Dual Quad Core Mac Pro). The CPU is the main component that dictates a machine's overall speed of operation. A slower CPU with an efficient instruction set may actually provide better performance than a faster CPU with a less efficient design.

Although the CPU is the master component in a computer, its function is easily understood. It takes data supplied by other components, moves it, does simple logical operations or math operations, and outputs the results. The magic lies in the vast amount of data processing it can do in a very short amount of time. Your CPU processes millions of instructions per second. Although each individual instruction is very simple, the fact that so many calculations are done so quickly allows your computer to perform extremely complex tasks within a reasonable amount of time.

TechTool Pro verifies the operation of your CPU chip(s) with both machine-level native instruction tests and more complex system-level data operations. When the Processor tests complete, the processor speed is displayed on the Processor gauge.


All Mac OS X capable computers include Ethernet networking capability. The ability to print, communicate with other computers in your local network, and connect to internet services is dependent on proper configuration and operation of the networking components.

Ethernet is the most widely installed local area network (LAN) technology. Ethernet was originally developed by Xerox and is specified in the IEEE 802.3 standard. An Ethernet LAN may be hardwired using a variety of cable types or it may be wireless. The most common Ethernet systems use 10Base-T cabling and provide transmissions speeds of up to 10 Mbps. Fast Ethernet or 100Base-T provides speeds of up to 100 Mbps, Gigabit Ethernet supports up to 1000 Mbps, and 10-Gigabit Ethernet goes all the way to 10 billion bits per second.

AirPort is Apple's name for the IEEE 802.11 wireless networking standard. The original AirPort implementation released in 1999 is based on the IEEE specification 802.11b. It transmits data at a maximum speed of 11 Mbps and has a typical range of 100 feet. The newer AirPort Extreme released in 2003 is based on the 802.11g specification. It has a maximum speed of 54 Mbps and range of 50 feet at full speed. The newest AirPort devices are based on the 802.11n protocol which increases performance even further to a maximum of 600 Mbps. Both AirPort and AirPort Extreme transmit on one of 11 channels in the 2.4 GHz band.

The Network test performs the following functions on the built-in network interface:

• Network Check 1—This test checks the availability of the network services for the system.

• Network Check 2—This test checks whether a network host name is reachable using the current network configuration.

noteNOTE It is necessary to have at least one other network device attached (printer, router, or another computer) to use these tests since it is necessary to query another device to determine communication abilities.

When the tests complete, the speed of the network interface is displayed on the Network gauge. For multiple network interfaces, the fastest one is displayed. If the test fails or if no network interface is detected, this will be displayed as well.

Note that TechTool Pro cannot test the networking hardware itself. This requires specialized test equipment. If the problem appears to be faulty hardware you will probably need to contact a qualified technician.


FireWire is a cross-platform implementation of the high-speed serial data bus defined by IEEE Standard 1394. FireWire was conceived by Apple and then developed within the IEEE 1394 Working Group. It can move large amounts of data between computers and peripheral devices. It features simplified cabling, hot swapping, and transfer speeds of up to 400 Mbps. The newer IEEE 1394b specification, termed FireWire 800 by Apple, handles data rates of 800 Mbps.

FireWire is integrated into most recent Macintosh models. Most of these machines include FireWire ports that operate at up to 800 Mbps, although earlier models may use the 400 Mbps interface. FireWire ports may also be added via PCI cards or FireWire hubs attached to existing ports.

The high data transfer speed of FireWire makes it great for use with multimedia peripherals such as digital video cameras and other high-speed devices such as hard disk drives and scanners.

TechTool Pro checks the built-in FireWire bus in your computer to ensure that it is functioning. Note that the program itself cannot check the FireWire ports to verify that data is being sent and received properly. This would require special loopback hardware not normally available.

If the tests pass, the speed of the FireWire interface is displayed in the FireWire gauge. If the test fails or if no FireWire interface is detected, this will be indicated on the gauge.

Manual Testing

To run any of TechTool Pro's manual tests, click the Tests tab if necessary to display the Test Selection window. Select a test from the Test Selection list and configure it as desired in the Test Configuration window to the right. Then click the Run button in the Configuration window to add the test to the test queue. An individual test can be stopped as it is running by pressing the Stop button on the lower right of the test icon in the queue.

stop_buttonAll queued tests can be stopped by pressing the large Stop button on the lower right side of the stage.

As a test runs, progress information is displayed on the stage. Upon completion of a test or group of tests, the results are displayed in the Job Results From Last Run window on the left side of the stage. Selecting a test from this list displays detailed test results on the right side of the stage. All test results are also stored in the TechTool Pro Report. The report can be viewed by selecting the Reports category. Details about the individual tests follow.


Check Computer Check Computer

In addition to the hardware checks that are done automatically at program launch, you can use Check Computer to easily run a more intensive group of tests to check other components of your computer, including drive and volume tests. You might consider using Check Computer once or twice a month as part of a program of preventive maintenance for your computer. Even though problems with your computer may not be apparent, they could be developing in the background. It is best to find and correct them at the first opportunity, before they become so severe that you lose data and/or they may no longer be correctable. All that is required to do a comprehensive suite of tests with TechTool Pro is one click of the mouse.

Choose Check Computer from the Tests category to bring up the Check Computer Configuration screen.

Check Computer Configuration

The Configuration screen displays an image of your computer with the computer model and date of manufacturer listed below (this information may not be available if the computer's logic board has been replaced). An icon for each hard drive attached to the computer appears to the right of the computer graphic. Hover the cursor over a drive icon to reveal a tooltip displaying the drive identifier, connection type, and volumes on the drive.

Click the Check Computer button to queue up and run all tests on the computer and all available volumes/drives. Feedback about the tests is displayed on the stage as the tests are run. Progress and result information are listed there.

TechTool Pro 6 Check Computer Stage

At the conclusion of the tests, all results are saved to the Report. Any test failures are listed there, along with advice on how to proceed.

The following tests are run by Check Computer.

• Memory Test—checks the computer's available RAM.

• Surface Scan—checks attached available hard drives for physical bad blocks.

• SMART Check—checks the built-in hard drive SMART parameters.

• Volume Structures—checks all attached available Macintosh formatted volumes for directory corruption. Note that this test cannot be performed on the current startup volume, since it requires unmounting the volume. Boot the computer and run the test from another location (such as an eDrive or the TechTool Pro DVD) to test the normal startup volume.

• Video Memory—checks the video RAM.

• File Structures—checks for specific file type corruption.

For further details about a test, refer to the specific test's description later in this manual.

TechTool Pro 6 Memory Test Memory Test

Random Access Memory (RAM) is one of the most important components in your computer. Because almost every operation done on a computer passes through RAM, its accuracy is critical to the proper operation of your computer. It is also one of the components most susceptible to damage and failure. This is because RAM upgrades are common and hence RAM is handled more than most other components. RAM is extremely susceptible to damage from static electricity and handling it can expose it to this hazard. Also, like any chip, RAM is susceptible to overheating and thermal fluctuations.

Most other failures on your computer are more obvious than a RAM failure. For example, if your hard drive begins to malfunction, you will probably start to see read and write errors appear via dialogs displaying messages like, "Could not write file because of a disk error." However, RAM errors are much less obvious since software uses different areas of RAM at different times. RAM problems usually manifest as unexplained and inconsistent crashes. There is no clear error message indicating a RAM failure.

RAM is very susceptible to damage. Static, heat and even normal air moisture can damage the RAM used to store your Mac's workspace. It is possible that damaged RAM will prevent your Mac from booting. However, the most common symptom of bad RAM is much more subtle. Usually, the symptom will be an inexplicable system freeze that is difficult to reproduce consistently. Conventional troubleshooting techniques won't isolate the problem. In fact, standard techniques will prove to be more frustrating since the problem appears only intermittently, leading you to believe you've solved it only to discover later that the problem still exists and manifests somewhere else.

Unlike physically damaged storage areas on your hard drive that can be remapped by software so that they are no longer used, faulty RAM bits cannot be mapped out of use. While a technician with adequate equipment and replacement components can repair a RAM module, the cost to do this would greatly outweigh the cost to replace the entire module.

TechTool Pro offers one of the most comprehensive Mac OS X software-based memory testers available for Macintosh. A wide variety of RAM tests allow you to check the available memory in your Macintosh computer. TechTool Pro uses special read/write test patterns designed to exercise the RAM in such a way as to pinpoint specific types of RAM failures. TechTool Pro performs the following tests:

• Address Fault—On the first pass, this test writes the address of each memory cell to that cell itself. On the second pass, the address is read and verified to ensure address space uniqueness.

• Checkerboard—This test makes four passes. The first writes a pattern (different for each run). The second pass read/verifies the pattern and writes the inverse of the original pattern. The third round travels downward back through memory as it reads/verifies the inverse and then writes the original pattern. Finally, the fourth round verifies the original pattern.

• Extended March C—This test uses a complex algorithm consisting of six passes through memory. It moves upwards through memory during the first three passes, writing and reading/verifying either zeroes or ones. The next two passes move downward, reading/writing ones and zeros again (alternatively). The final pass may travel either direction, verifying that the last write was successful. This test detects address faults, coupling faults, stuck-at faults, stuck-open faults, and transition faults.

• MATS++—This test makes three passes through memory. The first moves downward writing zeroes. The second moves upward, reading/verifying zeroes and writing ones. The third moves downward, reading/verifying the ones written in the last pass and then immediately writes/verifies zeroes at each cell.

• Moving Inversion—This test first moves upward through memory writing an alternating pattern of zeroes and ones. The second pass moves upward reading/verifying the pattern and then writing the inverse of the original pattern. The third pass moves downward through memory reading/verifying the inverse and then writing the original pattern. The fourth pass moves back down through memory reading/verifying the original pattern.

• Sliding (Walking 1's)—Since bytes are eight bits and this test uses two passes to write/verify each pattern and two passes to write/verify the inverse of each pattern, it makes thirty-two passes through memory in eight rounds. Starting with the bit pattern 00000001, each memory cell is written and read to verify the pattern. This pattern is then inverted to 11111110 and written/verified. Then the 1 is slid up one position and the process repeated for a total of eight rounds. This algorithm was chosen to ensure that each bit of a particular memory cell can hold and maintain the value opposite that of its neighboring bits.

Choose Memory Test in the Tests category to display the Memory Test Configuration screen.

Memory Test Config

Select the length of time you would like the test to run from the Duration pop-down menu and click the Run Memory Test to add the test to the test queue. Memory problems are often intermittent, so the longer the test runs, the greater the chance of detecting an existing memory problem.

As the tests run, a graphic of the memory configuration for your computer is displayed on the stage, including how the slots are populated and the type and size of any memory installed. In particular, the following information is shown:

• Slot identifier and whether or not a module is installed.

• Module size at that location (if present).

• Type of module at that location (if present).

• Module model at that location (if present).

The individual memory test that is running and the time remaining to complete the testing is shown in the upper left area of the stage.

TechTool Pro 6 Memory Test

If you wish to stop the test, click the cancel button on the memory test icon in the queue.

When the tests complete, the results will be displayed in the Memory Results area on the right side of the stage (along with a graphical representation of the results) and in the Job Results From Last Run pane on the left.

TechTool Pro 6 Memory Test Results

Upon completion of testing, the test results are saved to the Report.

Surface Scan Surface Scan

TechTool Pro can do a Surface Scan test of your hard drives to check them for bad blocks. Bad blocks are areas of media that cannot store data reliably. All hard disks have a few bad blocks when they are created. These are "mapped-out" by the manufacturer at the factory or when a drive is reinitialized using the "zero all data" option. Mapping out bad blocks stores their location in a "bad block table." Once a bad block is mapped out, data is no longer written to that defective area of the disk. Occasionally a good block will go bad. If this occurs in a block storing a file, the file may be corrupted.

The Surface Scan test in TechTool Pro scans your physical drives for bad blocks and reports if any are found. In addition, if a file resides in the area of a bad block, the program will let you know the file name. The Surface Scan test reads data from every block on the drive to check the integrity of the drive surface.

Choose Surface Scan from the Tests category to display the Surface Scan Configuration screen.

TechTool Pro 6 Surface Scan

All recognized hard drives are displayed on the left side of the configuration screen with any partitions on them indented to the right beneath the drive name. Select the hard drive or volume (particular partition on the hard drive) you wish to test from the list and click the Run Surface Scan button to add the test to the queue. As the test runs, the program scrolls live data being read from the drive across the disk drive image displayed on the center of the stage.

Surface Scan Running

NoteNOTE The Surface Scan test may take several hours to complete on large hard drives since it must read and check data from every block on the drive.

The pane on the left side of the stage displays information about the drive and test progress. This includes:

• Device description

• Device serial number (if available)

• Number of blocks on the device

• Number of blocks processed

• Elapsed time

• Estimated time to completion

If bad blocks are found, the pane on the right side of the stage displays the block number and, if a file resides in that area, the file name. This information will also be available in the Report once the test completes.

ATA and SATA are the most common types of hard drive. These are typically pre-installed in new Macintosh computers and are generally used in USB and FireWire enclosures. TechTool Pro should not normally report bad blocks for these types of drives. The drive controller in them automatically tries to map out bad blocks as they are encountered. It will do this unless either the bad block is in a critical area that cannot be mapped out at the moment or the bad block table is full. If this occurs, TechTool Pro will report a bad block and you will ultimately need to do a low level reinitialization of the drive. When the drive is reinitialized, the entire platter is accessible so that bad blocks can be mapped out if possible no matter where they occur.

warningWARNING Reinitializing a drive erases all data on the drive. If possible, be sure to backup your data before reinitializing.

You can use Apple's Disk Utility to reinitialize your drive. Be sure to choose the Security Option to "zero out data." Choosing this option will map out bad blocks, if possible, during the reinitialization. This may take several hours (depending on the size of your drive). If the reinitialization is successful, the drive should be fine at that point. We suggest, however, that you do a Surface Scan a few times in the next month or two just to be sure no new bad blocks are developing. If they are, then the drive is probably failing and you should consider replacing it. If a low level reinitialization fails, this indicates the drive is faulty and needs to be replaced.

Smart Check SMART Check

SMART stands for Self-Monitoring Analysis and Reporting Technology. This technology was developed through the efforts of the SMART Working Group (SWG), a consortium of major hard disk manufacturers, to increase the reliability of hard drives. SMART routines are now incorporated into most new hard disk drives. Although the SMART specification was developed by the SWG, each drive manufacturer uses their own proprietary routines in their drives. The routines monitor important drive parameters as a drive operates and stores the results in the drive's SMART registry. An examination and analysis of these parameters can aid in the prediction of drive failure. This could provide the warning you need to backup your data and repair or replace a drive before it fails. It is estimated that SMART monitoring can predict 70% of drive hardware failures before they occur.

SMART technology monitors a drive as it is used and looks for unusual behavior. The routines keep track of disk performance, bad sectors, calibration, CRC (data) errors, disk spin-up time, distance between the head and the disk, temperature, features of the media, heads, motor and servomechanism. For example, motor or bearing failure can be predicted by an increase in the drive spin-up time and the number of retries required to spin-up the drive. Excessive use of error correction routines could indicate a broken drive head or contamination on the head. Spotting these types of errors early may prevent future catastrophe.

The SMART specification also includes drive self-test routines that can be executed to verify that a drive is able to accurately read and write data. The TechTool Pro SMART routines execute a self-test on a drive as well as check on the results stored its SMART registry. Problems found in either of these areas indicate possible impending drive failure. This advance notice might give you enough time to back up your data before it becomes inaccessible.

Choose SMART Check from the Tests category to display the SMART Check Configuration screen.

Smart Check Config

Select the drive you wish to test from the drive list on the left. Click the Run SMART Check button to add the test to the queue. As the test runs, a pane on the left side of the stage displays the name of the device being tested, as well as any volumes residing on the device. A pane on the right displays a bar graph showing the results for each SMART parameter.

TechTool Pro 6 Smart Test Results

The graph lists each parameter identifier (if available from the specific drive manufacturer) followed by the parameter number (in parentheses). A green bar indicates that the parameter is well above the failure threshold. As it approaches the threshold, it turns yellow. When the parameter falls below the failure threshold, it will be shown in red. Upon completion of the test, the results are saved to the Report.

If a drive fails the SMART test and you continue to use it, be sure to keep good backups of the data on the drive. It is possible the drive will fail within the near future. If the failure happens within the drive's warranty period, you might want to consider contacting the drive manufacturer. They will typically replace the drive if it fails SMART.

NOTE SMART is only available for ATA or SATA drives. SCSI drives do not support SMART. FireWire and USB drive interfaces do not pass the SMART calls necessary to perform the SMART test routines even though the drive in the housing may be an ATA drive.

Volume StructuresVolume Structures

There are a number of invisible files, settings, and parameters that the Macintosh file system uses to locate files, free disk space, and for other maintenance and management routines on Macintosh volumes. These are known collectively as the "volume structures." The Catalog and Disk Directory are part of the volume structures. Among other things, the volume structures keep track of the folders and folder hierarchy on a volume, what files are stored on a volume, and where all the individual pieces that make up those files are located. Individual files may actually be stored in many pieces scattered about across the surface of a disk. Damage to a volume's critical data structures can result in lost or damaged files and may even necessitate a complete reinitialization of the volume (which will erase it).

Volume structure damage may manifest in a number of ways. It can appear as missing files or folders. It can show up as file corruption, so that you receive an error when trying to open a file or launch a program. It can lead to problems when trying to copy a file from one location to another or when trying to empty the trash. In the worst case it may make a volume unrecognizable by the system. Generally, volume structure problems get worse over time. It is best to catch them early when chances of recovery and repair will be greatest. For this reason it is a good idea to check the volume structures regularly (perhaps monthly) as part of a program of regular preventive maintenance.

TechTool Pro can scan your volumes for problems related to the numerous structures that are necessary for the volumes to function properly. TechTool Pro will analyze and can often repair problems in the following attributes of a volume:

• Boot Blocks—The boot blocks are created when a volume is blessed. If they are corrupted, you may not be able to boot the computer from the volume.

• Master Directory Block—This block of data is created when the volume is created and contains important data about the rest of the volume. It is present on all HFS volumes and is similar to the HFS+ Volume Header. Because most HFS+ volumes contain an HFS wrapper, they will contain a Master Directory Block.

• Volume Header—This block of data is created when an HFS+ volume is created and contains important data about the rest of the volume such as its name, number of files and folders, and the amount of free space available on the volume.

• Allocation File (Bitmap)—This file acts as the main directory. It keeps track of the blocks that are allocated for use and the blocks that are free.

• Extents File (B-Tree)—This file contains the extent data for the entire volume. Extents are the separate pieces that make up a discontiguous file.

• Catalog File (B-Tree)—This file keeps track of all the files and folders on the volume.

• Attributes File—This file tracks all of the attributes of each file and folder on a volume. Some attributes include whether the file is locked and the last time the volume was backed up.

• HFS Wrapper—The parameters within this file contain the information used by the computer ROM to determine what program will boot the computer. In almost every case, this will be configured to point to the System.

noteNOTE For a detailed explanation of the volume structures see the Macintosh File Systems section later in the manual.

Select Volume Structures in the Tests category to display the Volume Structures Configuration screen.

Volume Structures Configuration

Select the volume you wish to test and click the Run Volume Structures button to add the test to the queue.


NOTE In order to test the volume structures of a volume, it must be unmounted. This means that you cannot do a volume structure check of the current startup volume. To do this, you must reboot the computer and run TechTool Pro from another volume, such as from an eDrive or the TechTool Pro DVD.


NOTE TechTool Pro may be able to recognize and test volumes that are damaged and do not mount normally on the desktop.

As the test runs, feedback is provided on the stage.

Volume Structures Stage Running

The progress of testing and elapsed time is displayed in the Volume Structures pane on the left side of the stage. The particular area of the volume structures being examined is shown on the right side of the stage in the Validation Progress pane. When an individual test completes, the indicator to the right of the test will turn green if it passed or red if it failed. As the tests run, live data being read from the volume is scrolled across the drive displayed in the center of the stage.

If problems are found on a volume during testing, a failure message appears on the stage at the completion of testing and is also saved in the Reports. In the case of failure, be sure you have important data from that volume backed up (if possible). Then, proceed by using TechTool Pro's Volume Rebuild tool to attempt to repair the problem. If a volume structure problem cannot be repaired successfully, the next step would be to reinitialize the volume (using Apple's Disk Utility) and restore the data.

Video Memory Video Memory

VRAM (Video RAM) is memory that holds the image that is displayed on your computer's screen. Like the other critical components of your computer video circuitry, VRAM must always be fully functional for graphics to be correctly displayed. Damaged VRAM can cause missing bits, screen noise, system lock ups, or freezes.

The Video Memory tests employ the same tests that are used in the Memory tests. For test details please refer to the Memory Test section earlier in the manual.

Choose Video Memory in the Tests category to display the Video Memory Configuration screen.

Video Memory Config

Click the Run Memory Test button to add the test to the test queue. As the test runs, the computer's screen will display strange patterns and/or colors. This is normal. When the test completes, the results will appear on the stage in the Job Results From Last Run and the Video Memory Results panes.

Video Memory Results

The Video Memory test results are also saved to the Reports.

NOTE TechTool Pro tests the video memory for the main display. To check a second display you will need to designate it as the main monitor before testing. This is done via the Displays pane in the System Preferences.


File Structures File Structures

The File Structures test in TechTool Pro checks a variety of file types for corruption. The test checks each individual file to ensure it conforms to the specifications for that file type. If there is anything unusual, TechTool Pro lets you know which files may be corrupted. There is no way for TechTool Pro to repair a corrupt file, since there is no way to know what the correct data in the file should have been. If corrupt files are found, you should delete them and then restore them from a known good source.

NoteNOTE If a file is flagged during testing, this does not necessarily mean the file is bad. It simply means that there is something atypical about the file based on its file type. If you are having problems with the computer or with an application that might be effected by that file, consider temporarily removing it or replacing it with a new copy if possible.

TechTool Pro checks the file type specifications to ensure they are valid. It cannot check actual data held within the file itself. For example, TechTool Pro can check to be sure that a GIF graphics file meets all specifications for that file type. However, it is not possible to tell is some of the pixels within the graphic image are incorrect, which could cause the image to display incorrectly.

NoteNOTE A file's type is determined by its extension. This is a three or four character code appended after a period to the end of the file name. Mac OS X does not normally display the extension in the Finder (although you can change the Finder preferences to display this information). If a file has the wrong extension, the File Structures test will flag it since the file type will be mis-identified.

Choose File Structures in the Tests category to display the File Structures Configuration screen.

File Structures Configuration

The File Structures Configuration screen lists each recognized Macintosh formatted volume attached to the computer. Select the volume you wish to test. To the right of the volume selection area are three check boxes. Check the boxes to indicate the type of files you wish to check. The choices are:

• Check Databases (e.g. plist and xml files)

• Check Image Files (e.g. bmp, gif, jpg, png and tiff files)

• Check Time-base media (e.g. MPEG, MP3, PDF files)

Once you have selected the file type(s) you wish to test, click the Run File Structures button to add the test to the queue. As the test runs, feedback is provided on the stage.

File Structures Progress

On the left side of the stage the File Structures pane displays information and test progress, including:

• Volume

• Current State

• Number of files processed

• Number of problems detected

TechTool Pro tests the following file types:




Additional file types may be added in the future.

The full file path name of the file currently being checked is displayed below the drive graphic. The right side of the stage displays any problems detected and the names of the corresponding files. Hover the cursor over a filename to display the full path to the file. A complete list of problem files is saved to the Report after the test completes.

Upon completion of testing, the stage displays the results in the File Structures pane on the right.

File Structures Results

The volume name, number of files validated, and number of problems detected are listed in the File Structures pane. Select a filename from the File Problems Detected list on the right and press the Show File button bring up a Finder window with the selected file selected.