Here are video instructions for granting Full Disk Access in Techtool Pro when using macOS Mojave or greater. Granting Full Disk Access is required in order for Techtool Pro to perform many of its essential functions, including testing and repairing disks.

The instruction text reads as follows:

1. Open the Security & Privacy system preference in the System Preferences application.
2. Click on the padlock icon in the lower left corner of the Security & Privacy system preference and enter your administrator name and password to make changes.
3. Drag the Techtool “Hot Air Balloon” icon below into the Full Disk Access table.
4. Choose ‘Later’ when asked to quit TechTool Pro. Quitting TechTool Pro is not necessary.
5. Close the Security & Privacy system preference window.