How can I diagnose the following issue -- Basically every few hours SL on my 2010 MBP "crashes". The following is what I mean by that 1. UI is somewhat responsive, I can click on windows. Clicking in the upper bar does nothing 2. Applications will not start up, but their icons appear in the dock and bounce forever. 3. Most applications stop responding. Refreshing in Safari, for example, does nothing. 4. I need to hold the power button down to do a hard reset. So it's not a complete 'crash' where the system is frozen, but it might as well be. I brought my MBP in to the apple store and they ran a full diagnostic suite on it (twice) and didn't find anything. I run some custom vpn softare for one of my clients, which might be the culprit. I say this because a few times the window has come up to re-login to the vpn, and right after hitting the "Login" button, the crash happens. However, I have talked with the company's customer support and this is the first they have heard of an issue (this is a big company). Finally, in my system.log i see the following around the time of the crash. In this case, I had come back to my computer and simply tried to relogin. Code: Jan 4 18:12:17 xxx loginwindow: Login Window Started Security Agent Jan 4 18:12:17 xxx WindowServer: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Jan 4 18:12:17 xxx com.apple.WindowServer: Wed Jan 4 18:12:17 ildatch.home WindowServer <Error>: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged. Jan 4 18:12:17 xxx fseventsd: event logs in /Volumes/Time Machine Backups/.fseventsd out of sync with volume. destroying old logs. (6939 0 7509) Jan 4 18:12:17 xxx fseventsd: log dir: /Volumes/Time Machine Backups/.fseventsd getting new uuid: xxx (I added the xxx). This is very annoying. Would love to get some help in resolving this.