Incompatibility in Software
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Verify that your application is the most current version available and
fully compatible with your Macintosh model. Check with the software
manufacturers for information on the latest revisions, what version of the
system should be used with what version of the application, and
incompatibilities.
All INITs, programs, and System files must be compatible with each other.
You need to know the EXACT version of applications and INITs. For example,
Microsoft uses version numbers in the following sequences: 2.0; 2.00a;
2.00b; 2.00c; 2.00d. These represent Microsoft Works versions. Microsoft
Works 2.00a is a problem in the System 6.0.7 environment. Microsoft Works
2.00b is compatible with System 6.0.7. It isn't enough to state that
Microsoft Works 2.0 is a problem. The version numbers need to be EXACT.
Corrupt Files
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Any type of software may become corrupted. It can be very difficult to find
out which piece of software may be causing your problem. Following the
steps outlined in the "Troubleshooting System Bombs" section may be the only
way to discover the corrupted software.
Viruses
-------
The best way to combat viruses is with one of the many virus detection and
correction programs available today. Viruses haven't caused problems on
computers with the latest copy of a virus protection program installed.
You'll need to start your computer from a floppy disk containing a virus
detection program to fully check and "vaccinate" your hard disk. The
System file and other software may not be diagnosed or fixed if they are
running when the hard drive is checked. Once the hard drive has been
checked and cleared of any offending viruses, an INIT file that scans each
floppy disk as it is inserted will keep your system virus free. See the
discussion of "Co-processor not installed!" errors for some information on
the WDEF virus.
Hardware
--------
If hardware is the problem, you should take your system to an authorized
Apple dealer for a thorough diagnostic check. If problems continue after
you've explored all software situations, look at hardware -- particularly
memory or memory management.
It could be RAM or the logic board. RAM problems can show up after
warm-up. For example, a marginal SIMM's speed may be fine when cool but
slow down after warming up. All SIMMs do this to a certain extent, but you
may have a SIMM that crosses the Macintosh computer's tolerance threshold
when warm. The only fix for this is to replace the offending SIMM or
SIMMs. A similar problem could be happening within the memory manager's
circuitry on the logic board; the only possible fix is a complete logic
board replacement.
You may also have a SCSI problem, particularly if you have external SCSI
devices attached. This problem occurs most often when you have external
SCSI devices attached, but not turned on. You must turn on all SCSI
devices before starting the Macintosh, and you must leave them on until you
turn the Macintosh off. If you don't take these precautions, you can
introduce garbage onto the SCSI data line.
Improper termination of the SCSI chain also causes this problem. If your
SCSI chain is the source of your problem, be aware that the garbage on the
SCSI chain may have corrupted the hard drive's format. You'll need to
reformat your hard drive with either all the external SCSI devices removed
or all of them turned on.