Creating Mac bootable CD from download

Hi - if anyone can please comment/assist. This is an outstanding site & resource, but less so if I cannot make bootable CDs from the Mac OS's available. Specifically, I downloaded Mac OS 8.6, unzipped it and obtained the OISO file. Pretty straight forward I thought. On my macbook OS X, just burn the ISO file to CD. Worked fine, CD has all the correct files. But my legacy powermac that I need it for. But it will NOT boot, no issues with powermac, I can boot from a retail OS CD no issues. IS there something specific I need to do that I am missing to create a bootable OS CD from these files or on my Mac (OS 10.11.6)



  • The 8.6 image we have is a "hard drive image" and needs to be redumped. That is, some idiot a long time ago dumped it using Apple DiskCopy rather than an ISO tool, which stores only the Mac file volume and not boot information. This will actually boot on some emulators, but not on a real Mac.

  • Ah - thank you! So it's not me & my inability :) when you say "re dumped" I assume you mean a new file loaded for download, so there is nothing I can do at this point, correct? Is that something I should look for or not a priority? I'll try a different OS version - just so I know I can accomplish - but I do need OS 8.6 thanks for the reply.

  • Well, if you do come across a genuine 8.6 CD please do image it and send it up.

    If your machine can run an earlier version you might be able to load the earlier version and then run 8.6 from the CD as an upgrade.

    Also keep in mind that some Macs release just after 8.6 and before 9 may require machine specific versions of 8.6. (But if you have a mismatch it should tell you that version is not permitted to run on your Mac)

  • Do you know if "Universal Unstall" shows the same problem or not:

    Contents looks identical, but there are proper ISO, at least.

  • Thanks, I'll try that and let you know. I appreciate all the help.

  • The linked image seems to be a valid ISO file with proper ISO headers and boot info, just be aware that it is inside a MacBinary container, so it must be extracted first. I don't have a good way to test it, so let us know if it works on real hardware.

  • That one is a winner! Extracted fine on my macbook, burned the toast image to disk and boots my powermac 6500 no issues at all. Thanks again khim!

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