Fanboi complaints of a mystery data-munching Mac OS bug began well before the arrival of Snow Leopard, Apple's latest desktop operating system. Similar tales of woe date back to at least November of 2007, when Jobsian cultists were still using the previous Mac OS version, just plain Leopard.

This week, the web is awash with reports of new Snow Leopard users who saw their Mac "home directories" destroyed after logging into an OS "Guest account." Typically carrying the name of the user, the home directory includes all the standard user file folders, including Documents, Downloads, Music, Picture, and more. Fanboi howls of Snow Leopard distress appear on multiple threads across the Apple support forums (here, here, here, here, and here).

But it appears the same bug predates Snow Leopard (aka Mac OS X 10.6). Sebastian Mondial, a Hamburg-based journalist with the German News Service, reported what would appear to be an identical problem with a post to the Apple support forum on November 13, 2007. Mondial was hit after a clean install of just plain Leopard (version 10.5.1).

"It was kinda scary," he tells The Reg. "I had a [MacBook Pro] at the time - a big one. I was just playing around with a Guest account, but then I switched back to my regular account...and I had this freezing moment when I realized, 'Oh shit. It's deleting my data.'"

He did have Apple's Time Machine backup running, but five days of files were permanently lost. "I swore to never enable guest access again," he says.

Just days before Mondial's 2007 post, someone else had complained of much the same thing. And still others howled about similar experiences in response to his post.

But like recent Snow Leopard victims, Mondial was unable to reproduce the problem. As one recent poster puts it: "The randomness is what's most creepy," says one, "[I] agree that someone's got to be able to reliably reproduce the error or this may be a long fight."

That said, Apple has acknowledged the problem in a statement tossed to Cnet. We are aware of the issue, which occurs only in extremely rare cases, and we are working on a fix," it reads.

One Reg reader was told that a fix has already been rolled into a version 10.6.2 pre-release build seeded to developers. ®

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