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When you crash and burn: Some tips on troubleshooting



Author: Sue Goodin
Date: December 1989
Keywords: Macintosh system crashes bugs errors tips hints
Text: In the last issue of Tech Tidbits, we discussed how to record your observations when System crashes occur, as well as the systematic approach to troubleshooting crashes. Today, we'll examine potential crash causes and how to correct them. Any system crash could corrupt your application or System Software to some degree. If not corrected, this may continue until the problem is detected and corrected. The solution is to reinstall System Software and, as a matter of good habit, the application. It is usually wise to keep floppy disk copies of System Software nearby so that you can reinstall the System Folder after any serious crash. Incompatible add-on programs (i.e., INITs, cdevs, DAs) may leave residue "bits and pieces" behind after removal. Reinstalling System Software may correct this problem as well. Not all versions of System Software and application software are compatible. Most applications will clearly indicate what version of System Software is required for that program. If you are using an older version of System Software, you may experience problems. If you are running current System Software, but an old version of the application, you may also run into problems. Occasionally, when System Software is updated, a well-running application may fail to run or crash. Try reverting to an older version of System Software or, preferably, notify the software vendor of the problem. Inquire about the availability of a "patch" or upgrade. Some programs are memory intensive. If you are running under MultiFinder (which requires additional memory itself), you may discover that you simply don't have enough memory to open or run the application. Some programs may fail to open; others will open and run until you try to invoke an operation requiring additional memory. You might try to close another application to permit you to use the one that is crashing and/or to arrange to purchase more memory. In some instances, a situation may arise where a program requires a certain amount of "contiguous" memory. While the Finder may show that you have 1MB of available memory, and the program needs only, for example, 267K, you may not have all 267K of memory all in one chunk. Close any other active application, then launch the program in question. Occasionally, a complete Restart will be necessary. Your application may not have enough memory allocated to run correctly in certain conditions. Before launching the application, select the application by single-clicking on it. Select the GET INFO command from the File Menu to check the "Suggested Memory Size (K)" of the application. If the "Application Memory Size (K)" is less than the suggested size, increase to the recommended amount. If you have the correct allocation, try increasing it to see if that helps. Some System startup documents, such as INITs, cdevs and DAs, may not have been written to permit 100 percent compatibility with different System versions. If this is the case, a crash usually develops shortly after you install some new add-on or after you install new version of System Software. Your only recourse is to remove the offending add-on and pursue a long-term solution with the software publisher. The most telling clue to this problem is when you try to open a document by double-clicking or printing it from the desktop, rather than after first opening the application. The error message "Application is busy or missing" usually confirms this. This indicates that the application is in use (for instance, you are trying to run a single-user program on a network while someone else is running it); missing (it is corrupt or you've inadvertently trashed it); or the Desktop Manager resource is confused because it can't find the document's application file. Check and make sure the application is really on your drive. Launch the application and make sure that it is not corrupt. Then restart your computer while holding down the OPTION and COMMAND keys. You will then be asked if you wish to rebuild your disk's Desktop and be given the option to Continue or Cancel. Click OK (you can stop holding down the two keys at this point). The Desktop Manager will restore order by reconstructing the disk's Desktop directory. You should be able to continue without any problems. CORRUPTED APPLICATIONS The application you are trying to use may be corrupted. On a 3.5" diskette, this may occur if the floppy is damaged, eradicated or corrupted when stored in hot or cold areas, near magnets, etc. On a hard drive, a sector on the drive may become corrupted, or one or more of its files may have been accidentally deleted. Check for viruses too! Trash the application and reinstall. APPLICATION CONFLICTS Occasionally, you may run into applications, or a combination of applications, DAs, INITs and/or cdevs that simply refuse to coexist. They all are competing for attention within the CPU and may not work together correctly, if at all. This is difficult to troubleshoot because there may be many factors interacting with each other. The problem may be intermittent, occurring only if the applications were opened in a specific order or if a certain DA had been run prior to the application's launch, etc. Troubleshooting this type of problem may take some time until you identify the problem application(s). Remove any add-on programs that are contributing to the problem or don't run them concurrently. Get in touch with the software vendors for assistance. APPLICATION ECCENTRICITIES Applications may act peculiar when running under certain conditions. For example, they may not permit you to print their documents from the desktop. If other applications run as expected, review the problem application's documentation to see if you can find a clue. If not, the application is still suspect since everything else runs fine. Contact the software vendor. DOCUMENT LAUNCH DIFFICULTIES In rare occasions, an application document as it grows in size may become less and less MultiFinder friendly. For example, you may open up a document that is relatively small -- say 15K. You work on it, add enough information to enlarge the document size to 100K and save it. A day later, you try to open that same document and are told you don't have enough memory or receive some other error message. Restart your computer under Finder and try to reopen the document. If successful, your program may not be fully MultiFinder compatible. Discuss this problem with the software vendor. MULTIPLE SYSTEM SOFTWARE COPIES Multiple copies or versions of System Software will cause repeated and multiplesystem crashes, system freezes and overall major headaches. Never, under any circumstances, have more than one version of System Software on your hard disk or floppy disk. Learn good file management. The only files that belong in your System Folder are your System software, device drivers, INITs, cdevs and other related programs. If you find a System or Finder anywhere else, trash it. It is easy to clutter your hard drive with multiple copies of System Software. Every time that you copy software up to a hard drive, there is the potential to copy System Software with it. Many applications bundle Macintosh System Software. As a double check, get into the habit of periodically using the Find File DA under your Apple Menu. Search on all your connected drives for "System" and "Finder." If you find multiple copies, get rid of them. Keep System Software only in your System Folder. CASE CLOSED! The most useful troubleshooting aid for system crashes is a thorough understanding of the Macintosh System Software operation. These tips should better prepare you for such occurrences. Remember, software troubleshooting is a lot like detective work -- the more information you gather on a software "suspect" will allow you to solve the case easier! ----- Permission to use Tech Tidbits, in part or in whole by any group, organization, or on-line service must first be obtained in writing from Apple Computer, Inc. Third Party Products mentioned within this issue are provided for information purposes only: They do not represent an endorsement or recommendation by Apple Computer, Inc. All products cited in this issue are trademarks or registered trademarks of their respective vendors. Kirk Bodick: Editor-in-Chief Dan Camper: Associate Editor Sue Goodin, Mark Hansen, Michael Lee, Pete Markus, Bill Starnes, Scot Treadwell, Stephanie Watts: Contributing Editors Stephen Landis, Brian Scott, Peter Demers, Joel Altsman, Mike Martin, Sue Goodin, Jim O'Hare: Executive Review Board

Copyright © December 1989 by Sue Goodin


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