Owners of late 2012 Macs like the Mac mini, the new iMac or the MacBook Pro with Retina Display are reporting a major problem with their machines: they can’t re-install Mountain Lion or even re-install from a Time Machine backup if their systems get corrupted.
According to a busy thread on the official Apple Support forums first reported by Mac Trast, the issue means that if users try to re-install Mountain Lion, the launcher will spit out an error message saying that the Mac isn’t compatible with Mountain Lion.
This doesn’t just happen if you’re launching the Mountain Lion installer from OS X, it happens on the Recovery Partition as well, although Repairing Permissions there apparently solves the issue. The same is true for Time Machine backups restored using the Recovery Partition.
The issue seems to be a widely known one amongst third-party Apple support professionals and retailers, and follows a similar issue which prevented owners of late 2012 Macs from updating to the latest version of Mountain Lion, 10.8.2.
Hopefully, we’ll see this issue addressed soon, before too many people lose their systems. For what it’s worth, though, it seems like it’s probably a simple matter of updating a “compatibility check” file somehwere.
For more information, read MacTrast’s post in full.