When updates are released, either for macOS or Techtool Pro, it is a good idea to also make sure that your eDrive is up to date. Note that updating the macOS or Techtool Pro on your main startup disk won’t update your eDrive, because the eDrive exists on a separate partition.
Here are our recommendations for the best way to keep your eDrive up to date.
If the macOS is updated, it is best to remove and create a new eDrive. This is important because Techtool Pro operates through the ‘lens’ of the operating system, and any bug fixes released by Apple tend to help Techtool Pro work more effectively.
This is an extreme example, but say you haven’t updated your eDrive in quite a while, and your Mac is now running Mojave, while your eDrive still has Sierra installed. In this case, your eDrive wouldn’t be able to see your main startup disk in the Volume Structures test or Volume Rebuild tool, because Techtool Pro needs the underpinnings of Mojave in order to support the APFS file system utllized by that version of macOS.
If Techtool Pro is updated, you can generally start up from the eDrive and simply update Techtool Pro using the Check For Updates… menu item in the Techtool Pro menu. If the macOS version hasn’t changed, this is a much faster method of keeping your eDrive up to date.
On the opposite end of the spectrum, if both your startup disk and your eDrive are already running Mojave, then you likely can simply start up from your eDrive and tell Techtool Pro to check for updates (which it will proably do automatically). Since just Techtool Pro has changed, no other action is needed. However, it is worth pointing out, that you may still want to create a new eDrive even after a maintenance update (ie 10.14.5 to 10.14.6), as these updates often contain important security fixes.
Hopefully this helps you to be a more effective Techtool Pro user!