TITLE
    CD-ROM: "This disk is unreadable" Message
Article ID:
Created:
Modified: 		17927
6/12/95
2/4/00
TOPIC

    When I put a CD into my CD-ROM drive I get the message "This disk is unreadable by this Macintosh. Do you want to initialize the disk?" What does this message mean?

DISCUSSION

    When the CD-ROM drive will not recognize a particular type of CD, this usually indicates the CD-ROM software is not properly installed or is missing certain files. In some cases, the one or several of the CD-ROM "Access" files may be damaged or a third-party extension or control panel may be conflicting with the CD-ROM software. Try the following suggestions to resolve this issue:

    Make sure you have not started your Macintosh with the Shift key held down to turn off extensions. This disables the CD-ROM extensions too. Also make sure you have not disabled the CD-ROM extensions using the Extensions Manager or a similar third-party utility.

    Make sure that these files are in the Extensions folder of your System Folder:
    • Apple CD-ROM
    • Apple Photo Access (if you plan to use Kodak Photo CDs)
    • Foreign File Access
    • High Sierra File Access
    • ISO 9660 File Access
    • Audio CD Access
    If any or all of these files are missing, search your hard disk to see if they have been moved to a different location, then move the files back into the Extensions folder. You need to restart the computer after moving the files to the Extensions folder for the files to work properly.

    If these files have been deleted, reinstall the CD-ROM software from your Macintosh System CD or system disks, depending on which one came with your computer. If you have updated the system software to System 7.5.x, Mac OS 7.6.x, or Mac OS 8, install the CD-ROM software using the system CD or disks for the newer system software.

    If you do not have the option to custom install the CD-ROM software from your system CD or disks, you can download the Apple CD-ROM software from Apple's Software Updates sites on the Internet.

    Alternately, you may also reinstall the entire system software for your computer. This will restore the necessary CD-ROM files.

    If these files are damaged, move the CD-ROM files mentioned above into the Trash, empty the Trash, then reinstall the CD-ROM software. Restart and test to see if the CD mounts on the desktop.

    If the preceding steps fail to resolve your issue, an extension may be conflicting with the CD-ROM software. If you are running System 7.5 (see Note), open the Extensions Manager control panel and select "System 7.5 Only" from the Sets pull-down menu. There are similar sets in Mac OS 7.6.x and Mac OS 8.

    When you restart your Macintosh, only the extensions installed with System 7.5 load. Test your CD-ROM disks to see if they work, then add extensions and control panels back one at a time, restarting after adding each one to isolate which extension is causing the conflict.

    NOTE: If you are using an earlier version of System 7, you have to manually drag extensions and control panels out of the System Folder and restart each time to isolate the offending file.

    Once you isolate the conflicting extension, contact the software manufacturer or vendor for compatibility information, or disable the extension to resolve the symptom.


    This article was published in the "Information Alley":
    Volume II, Issue 6, Page 5

Document Information
Product Area: Peripherals
Category: CD-ROM
Sub Category: General Topics

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