Here is Micromat's advice:

You can trash the TechTool Protection folder in the Library/Application Support folder.

We suggest that you uninstall TechTool Pro 5, run a Repair Permissions on the startup hard drive, and then reinstall. Be sure to use version 5.0.6.

To uninstall, run the Installer and choose Uninstall from the pop-down menu on the main Install screen (instead of Easy Install).

TechTool Protection should save at most three backups for each configured volume--then delete the oldest when it makes a newer one. You can go to the TechTool Protection system preference pane under the Directory Backup tab to turn off saving of directory backups for any volumes for which you don't want them saved.

Thank You
Micromat Inc.
Technical Support Team

I will follow their advice and, if I don't post anything else, everyone may assume that the problem has been solved. A big THANK YOU to Hal and the others who have responded. cool



Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365