Yes, I know, Macs don't get viruses. Or so they say... Two systems in our studio crashed yesterday with identical symptoms. An OctoCore MacPro and an iMac both running 10.5.6.
It started on the MacPro. Applications started missing. The app file was still there, but the icon turned to the generic app symbol with a circle and line over it. The app contents had been deleted, but the app itself remained. It seemed to target pro apps first. AE, then FCS, then Photoshop. Then it hit Safari and Firefox. Then all the files on the desktop went. All of this happened in a matter of 5 min or less. By the time I was notified of what was happening, AE and FCP project files were missing. I immediately shut down the system before more was lost.
My coworker told me he had a bunch or work he hadn't backed up in a while. Almost 2 months worth. So we booted the MacPro in target disk mode on the iMac and transferred only necessary files including any remaining project files and user documents. As the transfer finished, files started disappearing off the iMac. Baffled, we unplugged both systems from the network, and it appeared as though the problem stopped. Files were not placed in the trash can, nor where they hidden. They simply disappeared.
So much had been lost on both systems I figured the best way to fix the problem would be a clean wipe and reinstall everything. Using target disk mode we erased the boot drive on the MacPro, writing 0s over all data. Its back and running and we are doing the same to the iMac right now. Apps have not yet been reinstalled, but there does not seem to be any problems so far.
An internet search has turned up nothing related. The guys at AppleCare said they've never heard of this.
Any thoughts? Virus? Severe data corruption? Something else?
Final Cut Pro Editor
Sounds like a good reason to update software on all your macs more often. That's nearly a year old version, with security holes that have been patched since then. Might not be a bad idea to put a nice fat time machine backup on the mac pro as well. I use a 2Tb Green Power WD drive in an avail slot on my mac pro. It doesn't back up my big media RAID, but it covers my OS and internal drives.
Next time you run into an issue like this, run software update. If it is a hacker/malware issue, and you're running exposed software, at least you'll eliminate all known back doors, which may further help you track down the source of your problem.