I received this note from Micromat Tech Support
You can proceed with using TechTool Pro 2 since we have tested version
2.5.1 with Mac OS 9 and noticed no serious issues. A new version of
TechTool Pro 2 will be released soon for full compatibility with Mac OS
9. If you would like to be automatically informed of MicroMat updates,
you should subscribe to MicroMat News:
1. Send a message to:
You must send the message from the email account that you wish to
2. Message body should say ONLY the following:
3. You'll receive confirmation of your free subscription and you'll be
automatically notified each time we release a new update.
Thanks for your understanding.
MicroMat Techical Support