I've seen a couple of crashes on my 2010 Air - it's started to hang while doing basic tasks, like browsing, watching a movie or sometimes while just displaying the desktop with no applications running. It doesn't seem to be a heat issue since I can play 3d games for hours sometimes without any problem. Today I started looking through the preferences panes for clues. When I got the the Accounts pane, I got an error box saying "Preferences Error - Could not load Accounts preferences pane". Hmm.. I checked the system log and found this: Code: 2011-04-25 19.16.50 System Preferences [NSPrefPaneBundle instantiatePrefPaneObject] (/System/Library/PreferencePanes/Accounts.prefPane): principalClass is nil. Does anyone know what causes this error? I started to suspect I needed to repair disk permissions or I had a bad SSD, so I started Disk Utility.. Only to get a new popup saying "Disk Utility could not be opened because of a problem". What!? I checked the logs again, but it didn't really help. Here's what I found: Code: 2011-04-25 19.08.22 [0x0-0x1f01f].com.apple.DiskUtility dyld: Symbol not found: _OBJC_CLASS_$_XSAction 2011-04-25 19.08.22 [0x0-0x1f01f].com.apple.DiskUtility Referenced from: /System/Library/PrivateFrameworks/ServerKit.framework/Versions/A/ServerKit 2011-04-25 19.08.22 [0x0-0x1f01f].com.apple.DiskUtility Expected in: /System/Library/PrivateFrameworks/ServerFoundation.framework/Versions/A/ServerFoundation 2011-04-25 19.08.22 [0x0-0x1f01f].com.apple.DiskUtility in /System/Library/PrivateFrameworks/ServerKit.framework/Versions/A/ServerKit 2011-04-25 19.08.22 com.apple.launchd.peruser.501 ([0x0-0x1f01f].com.apple.DiskUtility) Job appears to have crashed: Trace/BPT trap 2011-04-25 19.08.23 ReportCrash Saved crash report for Disk Utility version 11.5.2 (298.4) to /Users/erik/Library/Logs/DiagnosticReports/Disk Utility_2011-04-25-190823_MacBook-Air.crash I checked the app crashlog too, but it said the same thing. I'm starting to think the SSD drive is bad, but I can't check it properly without Disk Utility, that I can't start. I also tried copying the Disk Utility app from another computer to a new folder on the Air, but it still won't run. Does anyone have any idea what I could do next? I have no idea I've rebooted the Air with "D" pressed and ran the hardware diagnostic, but it didn't report any errors. Any help appreciated!