Sounds pretty horrific doesn’t it. One of my servers I’ve got here is running the Windows 8 Server Developer Preview version and this morning, it started to spontaneously reboot every 2 hours. This worried me initially as it has been 1000% rock solid since it’s installation. I dug into the event logs and the first thing I noticed was that it happened every 2 hours without fail. That told me it was something scheduled. I did some more digging and found that in fact it was a scheduled expiration of Windows 8 Server Developer Preview that was due to expire on April 8th (ok it’s April 9th here in Australia, but you get my point).
This Microsoft KB here also shows how to get a hotfix via Windows Update that will extend the expiration date through to Jan 15, 2013 – far longer than I need. In fact, next week I’m reinstalling this system with the latest Windows Server 8 beta, so it won’t be an issue. Installing this hotfix however got around the issue for me for the moment.