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downgrade imac g3 to os 8

660 Views 5 Replies Latest reply: Oct 9, 2012 11:37 AM by I0070190 RSS
I0070190 Calculating status...
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Aug 18, 2012 2:52 PM



I received a nicely preserved iMac G3 from a friend (PowerPC 350 MHz). It's running on OS 9.2.1. I remember the two of us playing "Creepy Castle" on this very computer and I would really love to make it usable again (for the good old times). The game is still on the HD but it  only runs in black and white. The monitor control panel won't allow to turn off the color. That was, if I remember correctly, only possible with OS 8.


Now I bought an Original System 8.5 (Package with CD) over the Internet as well as a System 8.6 Disk. Both Disks have Installers on it but OS 8.5 as well as OS 8.6 won't work. I am pretty sure that the original OS was Mac OS 8.5 or 8.6. Running the installers I get the reply that 'this program can't be used on your computer' (translated from German).


Can anyone help me to downgrade the iMac back to OS 8.5 or 8.6 and by that making me happy running Creepy Castle again?


Hope so...Kindly M.

  • Niel Level 10 Level 10 (234,255 points)
    Currently Being Moderated
    Aug 18, 2012 2:56 PM (in response to I0070190)

    If it's a Blueberry iMac, you need to use its original disks and not a retail package. If it's an Indigo iMac, that's not possible.



  • Jeff Level 6 Level 6 (11,160 points)
    Currently Being Moderated
    Aug 19, 2012 10:22 AM (in response to I0070190)

    The blueberry-colored iMac G3-350 shipped with OS 8.6, so it can't run any older version of OS 8 (8, 8.1, 8.5, or 8.5.1).  Sometimes, a retail/universal OS installer disk of the same version isn't compatible with a Mac that shipped with that version.  This occurs when the retail installer disk was produced before that Mac was released, so that some of the required system software components are missing from that retail disk.  The same could be true, when attempting to use another model Mac's Restore Disk.  If you have the indigo-colored iMac G3-350, it never ran anything older than OS 9.0.4. 

  • britny Level 1 Level 1 (125 points)
    Currently Being Moderated
    Aug 21, 2012 2:40 PM (in response to I0070190)

    if you think your local dealer actually has the disc i wouldn't worry about being laughed at. i really do hope you find a solution for this.


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