I have a box that has been running Windows 2008 Enterprise Server stable for over a year. It's the full install, Hyper-V is installed and runs a couple VMs. Yesterday the machine had an "unexpected shutdown". I looked through the event logs, and the last event (normal event) was logged approximately 30 minutes prior to the shutdown. No MEMORY.DMP or minidump file was created even though those options are enabled, leading me to believe it wasn't a crash. Basically I have no idea why the machine shut down, and I have no idea where to look as to find out what happened. I am the only one with a login to that machine, the password is very strong and not written down anywhere. It's unlikely someone else was able to log in and shut it down. In addition a message came up during start-up asking to enter a reason for the unexpected shutdown. The eventlog does have a 6008 error logged saying that: The previous system shutdown at 9:10:14 AM on 1/30/2009 was unexpected. Any thoughts?