Guest system Win 2008 R2 auto restarted issue

[vboxjimmy]

Recently I created a VM using latest VirtualBox 4.1.6 and extension pack. The guest OS is Win 2008 R2. I built 2 VMs. The installations were smooth without problems. However, both VMs got the auto-restarted issue. It normally occurred once around 12:33am. It didn't happen every day but almost once everyday. The event log shows:
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Source: Kernel-Power Level : Critical
BugcheckCode 26
BugcheckParameter1 0x41287

The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.
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My host OS is window 2007 64bit and has 12G memory. The VM has 4G memory. My other VM with win 7 32bit OS didn't have this auto-restarted problem.

I checked and uncheckd PAE setting, changed power option but didn't resolve the problem.

If any of you have this experience or have ideas, please let me know. Thank you very much!

jimmy

[BillG]

My guess would be that some piece of equipment which uses a lot of power starts up about then and causes a voltage drop on your power circuit.