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Macintosh Troubleshooting - Info Source: web.whittier.edu

Macintosh Troubleshooting

Boot the Macintosh with the "Boot" floppy disk/CD-ROM

If the computer displays the "Sad Mac" or something else goes wrong:

If the computer fails to boot properly, there may be a hardware problem. If the "Sad Mac" is displayed, the numbers and letters underneath it are error codes. They may be useful in determining what has gone wrong.

Make sure that there is nothing wrong with the boot floppy by testing it on another computer. Also make sure that all peripheral devices have been unplugged, and then try the boot floppy again. If the system still fails to boot, it is likely that there is a hardware problem. Refer users to the Computer Center for hardware repair.

If the computer's hard drive does not appear on the desktop, use the Norton Disk to check the drive for problems. Restart the Flowchart from the beginning.

If the Macintosh booted properly (Finder and desktop appear):

The computer's hardware is not the problem. Continue to follow the flowchart. (The next step assumes there is an internal hard drive; if there is no internal hard drive, or if the system volume is on an external drive, reattatch that device. Make sure that the SCSI chain is properly terminated; refer to the drive's documentation if you need help).

Restart the Computer

If the computer displays the "Sad Mac":

Because the computer booted successfuly when we used a startup floppy, the "Sad Mac" probably indicates a problem with the hard drive. The numbers and letters underneath the "Sad Mac" are error codes. They may be useful in determining what has gone wrong. The "Sad Mac Error Codes" application on "Support" may be used to decipher the error code. The hard drive's boot blocks may be corrupt, or there may be a problem with the System software. It is also possible that the PRAM is corrupted.

Turn off the computer and boot from the Norton Disk. Zap the PRAM when the system is booting, and repair any problems found on the hard drive. Repeat the Flowchart from the beginning.

If the computer displays the "Flashing Question Mark Disk":

When a Macintosh cannot find a bootable system disk with a blessed System folder, it displays this icon. If the hard drive connected to the computer has no system software on it, the computer will display this icon. It is more likely that the System software is on the drive, but it was not blessed or it is corrupted. It is also possible that the PRAM (that stores the location of the startup volume) is corrupted.

Boot with the Boot disk and zap the PRAM. Bless the System folder on the hard drive after the Finder loads. Restart the computer. If the "Flashing Question Mark Disk" icon remains, there is either a problem with the Hard drive or the System software on it. Turn off the computer and boot from the Norton floppy. Repair any problems found on the hard drive. If the "Flashing Question Mark Disk" icon still remains, reinstall the System software: If you install System 7.5, update the System using the lastest updater. Use the floppy disks or CD-ROM that came with the computer to resinstall the system. Repeat the Flowchart from the beginning.

If the computer display remains blank:

If the computer has a problem after the startup diagnostic, the stystem may freeze and not display an icon at all. This may be due to corrupted PRAM or boot blocks. Turn off the computer and boot from the Norton Disk. Zap the PRAM when the system is booting, and repair any problems found on the hard drive using Norton Utilities. Repeat the Flowchart from the beginning.

If the computer displays the "Happy Mac":

The "Happy Mac" indicates that the computer passed its self-diagnostic test and found the System software to load. Continue to follow the flowchart.

Wait for the "Welcome to Macintosh" dialog box

If the computer displays the "Sad Mac":

The Macintosh booted successfuly when we used a startup floppy, and displayed the "Happy Mac" when the Internal drive was used. If the "Sad Mac" appears afterwards, it probably usually indicates a corrupt system file. The Macintosh displayed the "Happy Mac" because it had located the System files on the hard drive and began loading them, but if the system software is corrupt, the system my freeze or display the "Sad Mac" shortly after it begins loading the System files.

Use the floppy disks or CD-ROM that came with the computer to resinstall the system. Repeat the Flowchart from the beginning.

If the computer displays a "System Software is too old; please use a current version" dialog box:

Usually, this error appears on Macintoshes running System 7.1 that do not have the appropriate Enabler file installed. Enabler files contain system resources that specific Macintosh models require, and are considered to be part of the system file itself by the operating system. When the computer cannot find the resources it needs in the System file (actually the enabler file), it gives this error; beliving the problem is an older version of the System software. Most current Macintoshes now require at least System 7 or System 7.1 in order to run, PowerMacs require System 7.5; they cannot use earlier versions because their ROMs no longer include all of the instructions and code used by the earlier systems. If the computer displays this error dialog, make sure it is using an appropriate version of the System software.

All of the enabler files released before the introduction of System 7.5 were incoperated into the System file itself; Clean installing the latest version of the MacOS should remove the error dialogue. If the user does not want to install System 7.5, the required enabler file should be on the "Install Me First" Disk that came with the computer. If the compuer was trying to use a version of the System software earlier than what it requires; resinstall the appropriate version. After installing System 7.5 or copying the enabler file into the System folder, restart the computer and repeat the Flowchart from the beginning.

If the computer displays the "Welcome to Macintosh" dialog box:

The "Welcome to Macintosh" indicates that the computer located the System files on the hard drive and has begun loading them. System versions later than System 7.1 display a progress bar to indicate the status of the startup process. System versions later than 7.5 should replace the "Welcome to Macintosh" dialog box with a "MacOS" screen. Continue to follow the flowchart.

Wait for the Extensions and Control Panels to finish loading

If the computer freezes, bombs, restarts, or displays the "Sad Mac":

If these problems occur while the Extensions and Control Panels load, it usually indicates an "extension conflict". Two or more of the System extensions are trying to patch the same system code, or are otherwise causing each other to do things they weren't designed to do. Something gets confused, and the computer crashes. It is also possible that one or more of the Extensions or Control Panels is corrupted, or incompatible with the System software itself.

When resolving extension conflicts, it is a good idea to first boot with the [shift] key held down. This allows the Macintosh to boot without loading any Extensions or Control Panels; if the computer boots normally and has no problems, the error was due to an Extension or Control Panel. There are several utilities to turn Extensions and Control Panels on and off; System 7.5 includes the "Extensions Manager" Control Panel do just that. There are commercial utilities that try to determine exactly what extensions caused the problem; without them it can be difficult to know just what Extension of Control Panel to turn off. Trial and error is usually the best way to determine where the problem lies: Turn off half of the Extensions and Control Panels and reboot. If the problem does not appear, then turn on half of the extensions you have left. When the problem reappers, you will need to reboot without any extensions, and then turn on all the extensions except for half of the group of extensions you just turned on. This can be repeated to narrow down the problem to a specific Extension or Control Panel. When you've found the problem file, delete it (or try reinstalling from the original disks). Once the System loads all of the Extensions and Control Panels without any problems, continue to follow the flowchart.

Wait for the Finder to finish loading(all disks mounted, startup items launched, file sharing finishes starting up if it is turned on)

If the computer freezes, bombs, restarts, or displays the "Sad Mac":

The Finder in System 7.0, 7.0.1, and 7.1 contains a bug known as the 'Finder Recycling' bug. The sympton of this is that at the very end of the startup sequence, whether you boot from the hard disk OR from a floppy disk, the Finder draws the menu bar and then restarts itself. This continual restarting of the Finder continues until you hold down <command>+<shift>+<mouse button>. Once these keys are held the Finder correctly launches and the problem goes away. The problem is caused by the Finder's attempts to open the windows that were open when the system was last shutdown. Sometimes the Finder fails to cache this data correctly, and when it attempts to re-read the corrupted cache it crashes. The system then relaunches the Finder, which attempts the same operations and crashes again, and again... The action of the keys is to instruct the Finder to present a clean desktop, with no open windows, therefore it doesn't read the cache and attempt to operate with corrupted data.

If a drive's desktop files are corrupted, the Finder may crash or freeze when it attempts to mount the disk. Reboot the computer and rebuild the desktop files.

The applications or files in the "Startup Items" folder may be buggy or corrupt, restart with shift key held down and remove all startup items. Replace them with fresh copies from the original disks.

If file sharing is turned on, crashes and freezes may be due to corrupt sharing preferences. Restart with shift key held down and delete the "Users & Groups Data file" from the "Preferences" folder. Use ResEdit or FileBuddy to make the "Sharing PDS" file (on the root level of the hard drive) visible and delete it. Restart the computer and reconfigure your file sharing preferences.

If the problem occurs after the Finder loads:

Seemingly random freezes, bombs, restarts, or error dialog boxes may be caused by a corrupted System file. If time and disk space is available, perform a clean System install. If the problem continues, remove all non-apple system Extensions and Control Panels. There may be a bug in one or more of them that is causing the problem.

If the problem still persists:

Back up all the data files on the Hard drive. Remormat the the hard drive using the disk utility that it came with and perform a Clean System Install. If you install System 7.5, update the System to the latest version using the floppy disks or CD-ROM that came with the computer to resinatll the system. Reinstall all applications from the original disks.