Apple Macintosh System 7.5 - Manual (Page 104)

4 Use the computer for a while and see if any problems occur.
If nothing goes wrong, then the extension or control panel is probably
compatible with System 7.5.
If your computer behaves erratically, then the program is probably
incompatible with System 7.5. Open the Extensions Manager and click the
program’s name to remove the check.
5 Repeat steps 1 through 5 for each item in the “May Not Work with System 7.5” folder that
you want to test.
100 Appendix C