Classic system prefs panel and vanishing volumes
Oct 11, '01 11:42:56AM
Contributed by: robg
Last night I decided to upgrade my "experimental" partition from 10.0.4 to 10.1. This is where I test things on OS X before committing them to my production box. As part of the process, I decided to split the drive into a few partitions, as I had a lot of unutilized space. So I ran Disk Utility, partitioned, installed 10.0, upgraded to 10.1, configured a bunch of stuff, and then booted back to my production 10.1 environment. When I went to select my standard Classic partition, this is what I saw:

There were two problems here. The first was that everything was greyed out, the second was that my normal Classic partition didn't even show up! They grey-out problem didn't surprise me, as none of the listed volumes have OS 9 installations. But there were at least three other partitions that did, and they were nowhere to be seen.
Things I tried to fix the problem included copying a 'good' OS 9 to the missing partition (no change); specifying the OS 9 partition as the Startup Disk (as it was visible there), then checking Classic again (no change); and booting on the missing partition and then restarting in 10.1 (no change). Finally I gave up and did a clean install of OS 9.1 and 9.2.1 on the missing partition. Restarted in X and ... no change! Argh!
To save everyone else a ton of time, you may not have to do what I did. At least in my case, the problem seems to have been caused by a bug in the Classic prefs panel, not any issue with Classic itself or my partitions. If you have more than a few partitions (I have about ten total across three drives), the Classic panel in System Prefs doesn't seem to display scroll bars or arrows ... and it didn't seem to respond to the arrow keys, either. After some random clicking in the box and moving my scroll wheel and hitting the arrow keys, I managed to get the box to scroll ... and found the "missing" Classic partitions off the bottom of the display area!
So if you think you've lost a bootable Classic from the Classic prefs panel and you have a large number of partitions, make sure it's not a scrolling problem before investing time in a more complex solution! I'll try to investigate a bit more over the weekend to see if I can figure out exactly when it will and will not scroll ... and I've filed a bug report with Apple :-).
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Mac OS X Hints
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