I am running 10.6.8 with all of the most recent updates on a MB. Last night I noticed I had two folders missing--unimportant files I thought I might have trashed. I upgraded my iPhone to iOS 5.1.1 and went to bed. This morning I looked for a number of files to work with and most of my folders had disappeared from my desktop and mostly from my Documents folder(~/user/documents). I have googled the issue and attempted the following: Verified disk--no problem detected Repaired permissions Deleted finder .plist file Checked SMART status--good Ran tests on hard drive and volume structure using Tech Tool Pro--no problems reported I have only my admin user account so I created another one with file sharing permissions--files do not show up. The files also no longer display under recent documents in Pages or similar programs. Finder cannot find the files and Speed Download cannot point to recently saved downloads. None of the files are in the Trash. No other hard drives were mounted or in use, so files were not accidentally misplaced. I have backups of 99% of my files from before this happened, so I can restore. Any other suggestions before zeroing out the hard drive? Overinstall SL first? Any ideas what caused this? Software or hardware issue?