[Static archival site for legacy owners] Mac OS 8 & 9 A general diagnostic procedure for Macintosh freezes and crashes Introduction This page answers the FAQ, "What can I try to keep my machine from freezing or crashing so much in order by level of desperation?" If you just finished reading the troubleshooting chapter of your favorite quick tutorial book and are now ready for something more that running Disk First Aid, you might like to try simple things first, like the suggestions in our Cribsheet,. Those issues that are more model or application specific are left to software like Conflict Catcher. Also see the fine explanations in Yale's Macintosh Guide for solving more general kinds of problems beyond crashing and freezing. These sources are especially valuable if you are a newcomer to the Mac. They can help with the most common software and hardware problems. More to the point of this page is the book Sad Macs, Bombs and Other Disasters by Ted Landau. A newer Edition has recently been published by PeachPit Press. Ted is the host of MacFixIt and author of the troubleshooting chapter in MacBible. CAUTION: If you don't backup your data and run your favorite disk doctor software very regularly, your worst nightmare may be awaiting you. Equally important is scanning your hard drive regularly. If your disk doctor utility finds an error and says it was fixed, it pays to run it again to see if it really did, in fact, fix the problem. If it didn't, consider restarting from an emergency floppy or a bootable CD and running it again. The author's favorite is Norton Utilities Disk Doctor by Symantec. One kind of preparation that will pay dividends eventually is to prepare a set of current, bootable emergency floppies or a bootable CD to keep on hand for troubleshooting. Minimally, have one floppy with your favorite disk doctor, one with Apple's Disk First Aid, one with your hard drive formatting software and finally, one with a virus checker. If you burn a custom bootable CD, you can fit them all on one CD. If you use backup/restore software, you may want a copy on bootable media. If you do a lot of troubleshooting, an additional disk with a hardware diagnostic tool, like TechTool Pro can also be helpful. Many other specialized utilities will be mentioned in this document along the way. At this time the single most helpful tool to control crashes during the restart process is Conflict Catcher. It is usually able to indentify trouble spots that cause a crash and allow you to selectively turn off items which might cause repeated crashes. Another kind of preparation is defensive driving, prevention through good work habits. Save your PRAM settings with a free utility like Techtool during a period when your machine is stable. In General, save your work frequently. Try out one new piece of software at a time, particularly control panels and extensions. Keep a current copy of your System, Finder and critical preferences handy, if you value them. If you have alternate media, make sure you have at least one bootable volume containing your current system software. Try to keep ten percent of the space on your system disk disk available at all times. If your only hard drive formatting software is what came with it several years back, make inquiries for getting something more current. If you have valuable data on a floppy and inserting it produces a message saying that it is unreadable, do not initialize it, lock it. Try to insert it in another drive or even in another Macintosh. If none are available, try it again after you have successfully inserted a second expendable floppy. If the floppy is substantially warmer or cooler than when it was written, it may be harder to read. You may have to try inserting it several times. Store your floppies in a low dust environment, preferably a container with a lid. If you are well prepared, your down time will be minimized. When a program crashes or freezes, unpredictable things can happen. PRAMs, boot blocks, and disk directories can become corrupted, so it is important to find and eliminate the cause in a timely way. The less you have to worry about recovering data, the more you can focus on getting things fixed. Our handy glossary is more than just a few quick acronyms and words, it was written specfically with troubleshooting in mind and is full of little tidbits and asides to help you be knowledgeable in the task of keeping your computer healthy. Think about reading it end to end. Crash vs Freeze vs Hang (as used on this site) After a crash your machine is useless until you restart, the keyboard has no effect, the mouse pointer will probably not move, the clock is not ticking (it is handy to have the seconds displayed on your menu bar clock to see this). During a freeze, your mouse will probably continue to work normally, the clock will be ticking away, but the keyboard will probably act as if it has been disconnected. If you here the drive churning away, your computer may just be really busy doing something. A hang is related to a peripheral, your computer will freeze or possibly crash when some device is turned on, or when software tries to access it or perhaps when a removable cartridge is inserted. Sometimes a hang will just go away when you disconnect or turn off the offending item, other times you will have to restart. Top | Crashes | Troubleshooting Links | Creme de la Mac | Cribsheet Simple Application Freezes (no bomb) If your keyboard or mouse goes dead, determine first if it really is a machine freeze or if only a mouse or keyboard hardware malfunction. First, be sure all affected cables are plugged in securely. If you use an alternate pointing device, like a trackball, it may freeze while the mouse is still functional! Substituting a different device that you are confident is working properly may solve the problem. NOTE! Technically speaking, it is not advisable to remove or insert any connectors associated with your Mac unless you first shut down completely, if you have ADB style connectors on your keyboard or mouse! It is possible to blow an internal fuse if you do. Another trick to outsmart mouse frost is to be able to Save in an application using a keyboard Command-S, very useful if just the mouse dies. In Netscape, for instance, I have additionally installed Command-S on the Save-As menu using ResEdit, for those many occasions when the Save command is dimmed. Only try this if you are comfortable with ResEdit. Other keyboard commands that may help depending on your situation are command-period to cancel a dialog box, command-W to close a window, or command-Q to quit. If the keyboard is also frozen, your options are more limited. You can hold down the command and option keys while pressing the Escape key to forcibly quit an application. Command-option-escape doesn't always work. If it never works and you want it to, use your extension manager to see if you might have installed an extension called NoForceQuit and disable it. If it still never works, try another keyboard, the Escape key may be dead. In any case restart your computer as soon as you are done saving any important work, if you are able to do so. The restart can be done via the power key on the keyboard, the programmer's reboot switch (triangle icon) or the main power switch. Each of these is actually very slightly different to the computer. If your crash of your machine is so complete as to be unaffected by pushing the power switch, you can try to hold it in for several seconds or simply unplug it. Powerbook users may have to remove the battery and unplug the power supply on occasion if they are unable to shutdown using either Command-Control-PowerKey or Command-Option-Control-PowerKey. You may notice a folder called Rescued Items in the trash. It is usually empty or contains useless material. If you are truly desparate, you can try looking at it with a program like CanOpener or BBedit. It is safest NOT to open WordTemp files with Word because it may hide certain material from your view. If you feel you must try, do it on a copy. You might like to read this and also this from Adobe. When a freeze happens while the machine is idle, be suspicious of an extension conflict. See the Extensions Conflicts/Bugs section below. If the freeze only happens only while printing a document, there may be insufficient memory to run the Print Monitor. You can try turning on Virtual Memory if it is off to see if the problem goes away. If this doesn't work, try a different printer driver if you have one or you can try increasing your Adobe Type Manager cache setting if the document being printed uses lots of fonts. Test the printing with background printing OFF. Verify that your LaserWriter driver is current. If your machine freezes or crashes each time you boot it and you have an unprinted document pending, an attempt to print may be the cause. To remedy this, restart the extensions off and double click the desktop printer icon with the X through it immediately. You will see a list of pending documents which you can select and drag into the trash. You can also just drag the icon itself into the trash. Sometimes a freeze will happen exclusively with a certain CD or floppy. For CDs this may be caused by some kind or dirt or gummy build-up that can be removed with careful cleaning using a solvent like Goo Gone. For a floppy, it may be time to run a recovery program to salvage what data can be saved, before you discard it. If the recovery fails, you can try copying the whole disk to a blank disk with a utility like Norton's Floppier or try opening any important files directly from the File menu using the program that created them. If you are unusually low on disk space, your machine may begin to freeze sporatically. Unknown to the user, many programs create invisible temporary scratch files as part of normal functioning. If there is not enough disk space to create these files, your computer may freeze or even crash as it slips into desperation. If you want to scour your hard drive of such remnants, you can try a program like File Buddy. Be aware that some invisible in the Preferences Folder are meant to be permanent user registration files put there to keep you from having to reenter your serial number each time you use a program. Defrosting Software Sometimes the keyboard and mouse become erratic. If you have an older Macintosh that does not have the newer USB connectors on the mouse or keyboard, you might want to try FocusBusTool. The MouseJolt application tells the Mac to try harder to use your pointer TSM Fix may help the reliability of your mouse by keeping you from experiencing "missing clicks". USB prober is of more limited use, but will give a list of recognized devices if you have a USB keyboard and mouse. If the freezes only occur when using a certain program, there are more ideas to try in the When you get to the Desktop) section. For freezes during the restart process, see the next sections. Top | Freezes | Crashes | Troubleshooting Links | Creme de la Mac | Cribsheet HOME Email to crashtips@crashtips.com (not for personal advice) updated 12/2001 The information on this page may be used and distributed freely in electronic form, so long as its source is cited. Any trademarks mentioned on these pages are the property of the respective trademark owners. Disclaimer: These ideas are for informational purposes only and constitute neither an endorsement nor a recommendation. CrashTips assumes no responsibility with regard to the selection, performance, or use of these products or vendors. All understandings, agreements, or warranties, if any, take place directly between the vendors and the prospective users. CrashTips makes no warranties as to the completeness or accuracy of this information. What you do to your computer is your choice and your risk. If you are a film "fogger" or streetlights go out when you walk by them, it may simply be best not to use a computer. Our best information comes from you the reader to promote informed self-help for others. The ideas expressed are merely opinions of the author and generous contributors to this page. Click every day to help the hungry.
This page answers the FAQ, "What can I try to keep my machine from freezing or crashing so much in order by level of desperation?" If you just finished reading the troubleshooting chapter of your favorite quick tutorial book and are now ready for something more that running Disk First Aid, you might like to try simple things first, like the suggestions in our Cribsheet,. Those issues that are more model or application specific are left to software like Conflict Catcher. Also see the fine explanations in Yale's Macintosh Guide for solving more general kinds of problems beyond crashing and freezing. These sources are especially valuable if you are a newcomer to the Mac. They can help with the most common software and hardware problems. More to the point of this page is the book Sad Macs, Bombs and Other Disasters by Ted Landau. A newer Edition has recently been published by PeachPit Press. Ted is the host of MacFixIt and author of the troubleshooting chapter in MacBible.
CAUTION: If you don't backup your data and run your favorite disk doctor software very regularly, your worst nightmare may be awaiting you. Equally important is scanning your hard drive regularly. If your disk doctor utility finds an error and says it was fixed, it pays to run it again to see if it really did, in fact, fix the problem. If it didn't, consider restarting from an emergency floppy or a bootable CD and running it again. The author's favorite is Norton Utilities Disk Doctor by Symantec.
One kind of preparation that will pay dividends eventually is to prepare a set of current, bootable emergency floppies or a bootable CD to keep on hand for troubleshooting. Minimally, have one floppy with your favorite disk doctor, one with Apple's Disk First Aid, one with your hard drive formatting software and finally, one with a virus checker. If you burn a custom bootable CD, you can fit them all on one CD. If you use backup/restore software, you may want a copy on bootable media. If you do a lot of troubleshooting, an additional disk with a hardware diagnostic tool, like TechTool Pro can also be helpful. Many other specialized utilities will be mentioned in this document along the way. At this time the single most helpful tool to control crashes during the restart process is Conflict Catcher. It is usually able to indentify trouble spots that cause a crash and allow you to selectively turn off items which might cause repeated crashes. Another kind of preparation is defensive driving, prevention through good work habits. Save your PRAM settings with a free utility like Techtool during a period when your machine is stable. In General, save your work frequently. Try out one new piece of software at a time, particularly control panels and extensions. Keep a current copy of your System, Finder and critical preferences handy, if you value them. If you have alternate media, make sure you have at least one bootable volume containing your current system software. Try to keep ten percent of the space on your system disk disk available at all times. If your only hard drive formatting software is what came with it several years back, make inquiries for getting something more current. If you have valuable data on a floppy and inserting it produces a message saying that it is unreadable, do not initialize it, lock it. Try to insert it in another drive or even in another Macintosh. If none are available, try it again after you have successfully inserted a second expendable floppy. If the floppy is substantially warmer or cooler than when it was written, it may be harder to read. You may have to try inserting it several times. Store your floppies in a low dust environment, preferably a container with a lid. If you are well prepared, your down time will be minimized. When a program crashes or freezes, unpredictable things can happen. PRAMs, boot blocks, and disk directories can become corrupted, so it is important to find and eliminate the cause in a timely way. The less you have to worry about recovering data, the more you can focus on getting things fixed. Our handy glossary is more than just a few quick acronyms and words, it was written specfically with troubleshooting in mind and is full of little tidbits and asides to help you be knowledgeable in the task of keeping your computer healthy. Think about reading it end to end.
After a crash your machine is useless until you restart, the keyboard has no effect, the mouse pointer will probably not move, the clock is not ticking (it is handy to have the seconds displayed on your menu bar clock to see this). During a freeze, your mouse will probably continue to work normally, the clock will be ticking away, but the keyboard will probably act as if it has been disconnected. If you here the drive churning away, your computer may just be really busy doing something. A hang is related to a peripheral, your computer will freeze or possibly crash when some device is turned on, or when software tries to access it or perhaps when a removable cartridge is inserted. Sometimes a hang will just go away when you disconnect or turn off the offending item, other times you will have to restart.
If your keyboard or mouse goes dead, determine first if it really is a machine freeze or if only a mouse or keyboard hardware malfunction. First, be sure all affected cables are plugged in securely. If you use an alternate pointing device, like a trackball, it may freeze while the mouse is still functional! Substituting a different device that you are confident is working properly may solve the problem.
NOTE! Technically speaking, it is not advisable to remove or insert any connectors associated with your Mac unless you first shut down completely, if you have ADB style connectors on your keyboard or mouse! It is possible to blow an internal fuse if you do.
Another trick to outsmart mouse frost is to be able to Save in an application using a keyboard Command-S, very useful if just the mouse dies. In Netscape, for instance, I have additionally installed Command-S on the Save-As menu using ResEdit, for those many occasions when the Save command is dimmed. Only try this if you are comfortable with ResEdit. Other keyboard commands that may help depending on your situation are command-period to cancel a dialog box, command-W to close a window, or command-Q to quit.
If the keyboard is also frozen, your options are more limited. You can hold down the command and option keys while pressing the Escape key to forcibly quit an application. Command-option-escape doesn't always work. If it never works and you want it to, use your extension manager to see if you might have installed an extension called NoForceQuit and disable it. If it still never works, try another keyboard, the Escape key may be dead.
In any case restart your computer as soon as you are done saving any important work, if you are able to do so. The restart can be done via the power key on the keyboard, the programmer's reboot switch (triangle icon) or the main power switch. Each of these is actually very slightly different to the computer. If your crash of your machine is so complete as to be unaffected by pushing the power switch, you can try to hold it in for several seconds or simply unplug it. Powerbook users may have to remove the battery and unplug the power supply on occasion if they are unable to shutdown using either Command-Control-PowerKey or Command-Option-Control-PowerKey.
You may notice a folder called Rescued Items in the trash. It is usually empty or contains useless material. If you are truly desparate, you can try looking at it with a program like CanOpener or BBedit. It is safest NOT to open WordTemp files with Word because it may hide certain material from your view. If you feel you must try, do it on a copy. You might like to read this and also this from Adobe.
When a freeze happens while the machine is idle, be suspicious of an extension conflict. See the Extensions Conflicts/Bugs section below.
If the freeze only happens only while printing a document, there may be insufficient memory to run the Print Monitor. You can try turning on Virtual Memory if it is off to see if the problem goes away. If this doesn't work, try a different printer driver if you have one or you can try increasing your Adobe Type Manager cache setting if the document being printed uses lots of fonts. Test the printing with background printing OFF. Verify that your LaserWriter driver is current.
If your machine freezes or crashes each time you boot it and you have an unprinted document pending, an attempt to print may be the cause. To remedy this, restart the extensions off and double click the desktop printer icon with the X through it immediately. You will see a list of pending documents which you can select and drag into the trash. You can also just drag the icon itself into the trash.
Sometimes a freeze will happen exclusively with a certain CD or floppy. For CDs this may be caused by some kind or dirt or gummy build-up that can be removed with careful cleaning using a solvent like Goo Gone. For a floppy, it may be time to run a recovery program to salvage what data can be saved, before you discard it. If the recovery fails, you can try copying the whole disk to a blank disk with a utility like Norton's Floppier or try opening any important files directly from the File menu using the program that created them.
If you are unusually low on disk space, your machine may begin to freeze sporatically. Unknown to the user, many programs create invisible temporary scratch files as part of normal functioning. If there is not enough disk space to create these files, your computer may freeze or even crash as it slips into desperation. If you want to scour your hard drive of such remnants, you can try a program like File Buddy. Be aware that some invisible in the Preferences Folder are meant to be permanent user registration files put there to keep you from having to reenter your serial number each time you use a program.
Defrosting Software
Sometimes the keyboard and mouse become erratic. If you have an older Macintosh that does not have the newer USB connectors on the mouse or keyboard, you might want to try FocusBusTool. The MouseJolt application tells the Mac to try harder to use your pointer TSM Fix may help the reliability of your mouse by keeping you from experiencing "missing clicks". USB prober is of more limited use, but will give a list of recognized devices if you have a USB keyboard and mouse.
If the freezes only occur when using a certain program, there are more ideas to try in the When you get to the Desktop) section. For freezes during the restart process, see the next sections.
Email to crashtips@crashtips.com (not for personal advice)
Any trademarks mentioned on these pages are the property of the respective trademark owners.
Disclaimer: These ideas are for informational purposes only and constitute neither an endorsement nor a recommendation. CrashTips assumes no responsibility with regard to the selection, performance, or use of these products or vendors. All understandings, agreements, or warranties, if any, take place directly between the vendors and the prospective users. CrashTips makes no warranties as to the completeness or accuracy of this information. What you do to your computer is your choice and your risk. If you are a film "fogger" or streetlights go out when you walk by them, it may simply be best not to use a computer. Our best information comes from you the reader to promote informed self-help for others. The ideas expressed are merely opinions of the author and generous contributors to this page.
Click every day to help the hungry.