Just thought I’d write down the result of some troubleshooting I did last night. My Vista box just stopped going to sleep. I first thought it might have to do with the fact that I installed SyncToy and set up a recurring Task in the Task scheduler that was also set to wake up the computer at 5 AM on a Sunday, and perhaps there was some bug with the RTC on my motherboard that caused things not to work.

But nope. A quick google led me to this forum post. Turns out, if you turn on library sharing in Windows Media Player, there’s a power management policy that says what to do when sharing is enabled, and by default that setting does not let you go to sleep when sharing is on.

I guess that makes sense. By the way, that was totally sweet. I just did an Alt+PrintScreen and then pasted into Windows Live Writer.

No OS so far has done what it really should do though.. actually report why the machine won’t go to sleep. If a user goes through the trouble to hit the sleep button or otherwise manually trigger a sleep, I’m sure they wouldn’t mind a dialog box telling them why what they just asked for didn’t happen.