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Troubleshooting Using TechTool Pro

Preventive Maintenance

One of the most valuable functions of TechTool Pro is its ability to assist you in finding and repairing problems with your computer before they get out of hand. For maximum protection, it is important that TechTool Pro is actually installed on your system. TechTool Pro includes automatic features that can regularly check your drive hardware and backup volume directories. These features are configurable from the TechTool Protection pane in the

System Preferences

In addition, it is a good idea to run the TechTool Pro tests on a regular basis (for example, monthly) to more thoroughly check your system. This will help ensure that your computer is running at its full potential and minimize the chance of crashes and data loss. Using TechTool Pro's Check Computer you can quickly and easily run a comprehensive set of tests to check your computer for proper operation.

It is critical to keep backups of valuable data. A hard drive will always fail at some point. Although TechTool Pro can often recover your data or bring your drive back to life when this happens, it cannot do the impossible. If the drive has failed mechanically or electronically, then no software can repair it. The insurance and peace of mind provided by a backup is important. A little time spent maintaining backups and checking your system regularly may save you many hours of recovery and repair down the road.

Troubleshooting Hints

Computers are complex electronic devices. Consequently, they can be difficult to troubleshoot. Their proper operation depends on the reliable functioning of both sophisticated hardware and software. TechTool Pro was designed to simplify the process of diagnostics and repair in the event of a computer problem. It can also help you find and correct small problems before they become big problems.

Be sure to backup your data regularly. Consider keeping archival backups. This means that instead of having only one backup you would keep several backups made on different dates. That way if you should discover a file was damaged, and was backed up damaged, then you might be able to locate an undamaged version in a prior backup. It is critical to keep backups since a drive may develop a problem at any time. If the problem is an electronic problem, a mechanical problem, or a volume structure problem that is so serious that it can not be repaired or the data recovered, then a valid backup would be your only recourse.

Following are a few tips to help ensure that your computer is up and running as soon as possible if problems do arise:

Backup Before Repairing

If you are experiencing problems, be sure your backups are current. If possible, immediately backup any important data that is not already saved elsewhere. You may need to use the data recovery routines in TechTool Pro to do this if your volume does not mount. Do this before performing any repairs. It may be impossible to retrieve your data later if the problems get progressively worse as the computer is used.

Be Prepared

Set up a preventive maintenance routine so that you can locate and address problems before they get too serious. Know where the TechTool Pro DVD is stored in case you need it. Consider using TechTool Pro to set up an emergency eDrive on your hard drive before problems arise. That way you can boot and run the program from the eDrive in the case of problems on your normal startup volume. Keep current backups of your work. Know where to find your TechTool Pro serial number in case you need to call Micromat Technical Support.

Eliminate Easy Problems First

Use TechTool Pro to repair the startup disk's permissions. Log out and then log back in as a different user and see if the problems still occur. There may be a corrupted preference in the original user's account. Start up the computer in Safe mode (holding down the shift key during startup). This disables third party routines that may be causing problems during startup. Run TechTool Pro's Check Computer while booted to the TechTool Pro DVD to see if it reports any problems. It's possible one of the above items will help pinpoint or solve the problem.


Eliminate as many variables as possible. If your problem appears to be with an internal volume, then power down your machine and disconnect all external devices. If it is with an external drive/volume, then connect only that drive to the computer. Startup and run TechTool Pro from the TechTool Pro DVD or the eDrive. This will eliminate the possibility of system corruption on your normal startup volume when testing.

Keep Your Software Up-to-Date

Many computer problems are actually software problems. The producers of most software release regular updates to address incompatibilities and other issues that they discover. Do your best to have current versions of software, drivers, etc. Staying current may keep problems from developing in the first place. Updating an older piece of software may actually solve a nagging problem.

Make Use of Available Resources

There are many sources of assistance available to help you solve problems. These include local Macintosh Users Groups, specialized newsgroups on the Internet, websites, listservs, and technical support provided by software and hardware vendors.

Document What You Do

As you try to solve your computer problems, keep notes about what you do and the outcomes of these actions. This can be a valuable reference for you later and can be extremely helpful if you need to talk to a technical support representative. Knowing exactly what was done and the results (including any error messages) can make problem solving much easier. In addition, if you have problems at a later time, you may be able to spot a pattern that would otherwise elude you.

Recovering Data from Damaged Drives

Files are more likely to be recoverable by TechTool Pro's data recovery routines if its automatic Protection features have been enabled for your volumes. Configure these options within the TechTool Protection pane of the System Preferences.

Repairing Drive Problems

You probably already understand how critical the proper operation of your hard drive is for your computer. It contains the data that allows the computer to boot, as well as the programs you use and the files you've created. TechTool Pro includes powerful diagnostic and repair routines to keep your drives functioning correctly.

In most cases, this manual will refer to a drive as a "volume." A volume is simply a unit of storage that appears to the computer as one "logical device." The terms "hard drive" and "volume" are almost interchangeable. Although a hard disk can contain more than one volume (multiple partitions), a volume cannot contain more than one hard drive. (This is not entirely true. Some forms of RAID disk setups can make many drives appear as one volume). DVDs and CDs may also appear as one or more volumes.

When you view the contents of a volume in the Finder, you're not typically seeing everything on the volume. Every volume contains many invisible files and data files. This allows the computer to access the data on that particular volume. Items such as the file catalog or directory, the extents B-tree, and a host of other objects, dictate how data is stored on a particular device (see the Glossary section of this manual for definitions of these terms). These items comprise the "volume structures" of a volume. In most cases, when a drive fails and then is repaired by a utility such as TechTool Pro, it is not the physical drive itself that is being repaired. It is the software that makes up the volume structures. If there is a problem with the structure of a volume, it can prevent the computer from being able to boot or prevent you from having access to your data. If there is an actual problem with the physical drive, like an electrical or mechanical problem, software will not be able to correct the problem. TechTool Pro is unique in that it can check the mechanical and electronic aspects of a drive, as well as repair the volume structures.

To check for disk problems, run the Surface Scan test, the SMART check (if applicable), and the Volume Structures test. These tests do a thorough check of the drive hardware and should locate any problems within a volume's directories. If TechTool Pro finds problems, it will let you know and provide advice on how to proceed. It would be wise at this point to stop and make a backup of your important files if necessary. If the problem was a volume structure problem, you could attempt to repair it using the Volume Rebuild tool in TechTool Pro. If it appears that a repair is possible, TechTool Pro will provide feedback about the changes it proposes to make. If you're satisfied that the proposed repairs appear reasonable, then go ahead and accept them.

After a successful repair the volume will be in good shape. If the volume structures cannot be repaired, you should reinitialize the volume and restore your data.


In order to gain maximum performance from a hard drive volume, it is a good idea to defragment/optimize it occasionally. This can be particularly important when working with multimedia files where maximum data throughput is critical. If a multimedia file is fragmented, then it may not be able to be read fast enough from the drive for smooth playback. This can lead to dropped video frames or to gaps in audio playback.

Optimization rearranges the data on the volume so that the data for each file resides sequentially on a contiguous area of the drive and the free space is consolidated. Optimization is available in the Tools section of TechTool Pro. Before optimizing, always check the volume structures of the volume (and repair if necessary). The volume structure tests are found in the Tests section of TechTool Pro. Once the volume passes the volume structure tests it should be safe to optimize it.

Testing Components

For your computer to operate correctly its components must be working properly. TechTool Pro includes a number of tests that will exercise many of the chips and other critical components of your system and let you know if any problems are found. You can easily check your computer's memory, cache, processor, video memory, and much more. Many of these tests are run when TechTool Pro launches. Others, such as the Memory Test, can be performed from within the Tests area of the program.