If your system bombs, proceed as follows:
1) Restart your Macintosh while holding down the Shift key, and release it
when the desktop appears. This action causes most of your system
extensions (INITs) and control panels not to load when the system boots.
(Note: In System 7, INITs are referred to as "system extensions.") After
you have removed your INITs and control panels, take each one,
one-by-one, and drag it to the System Folder and restart. If the system
bombs again, you will be able to tell which INIT, control panel, or
combination of them is causing the crash.
2) Open your System folder and remove all of your extensions and control
panels by placing them in a separate folder outside the System Folder.
Examine the system extensions and verify that you are using the current
version. If necessary, contact the product developer to determine which
is the current version.
If your Macintosh computer still does not start up, continue to step 3.
3) Restart from one of the System 7 floppies. In the System 7 disk suite,
the bootable floppy is the "Disk Tools" disk (both 800K and 1.4M).
4) Move any fonts, desk accessories, extensions, control panels, and
preference files that you want to keep from the System Folder to another
folder on your hard disk. Drag the remainder of the System Folder to the
trash and empty the trash.
5) Do a "clean" install of the software by following the installation
guidelines in your "Macintosh User's Guide."
If your Macintosh computer still does not start up, contact your dealer.