Sunday, January 31, 2010

Computer reboots every hour at the same time

Most times technicians fix a problem but do not really know the cause. A customers computer was shutting down. The first thing to ask is if it reboots itself or does it just shutdown completely. In this case the computer (A Vista machine) restarts. If a computer shuts down completely then it is a hardware issue. If a computer restarts then it is probably a blue screen (BSOD) that flashes by too quickly to see.
To investigate the blue screen the first thing we do is look at the system event log. The log most times captures the stop code of the failure. A good reference for all stop codes is Also we go into the system settings to stop the automatic restart. This lets the bluescreen remain on the monitor long enough to get some details and hopefully point to a file that is causing the problem.
In this case there was unfortunately no event log item for the failure just a note saying that the last shutdown was unexpected. What was interesting though was that the failures occured hourly at 43 minutes after the hour. this definitely looked like a software issue. I then checked the scheduled jobs for an hourly job without luck. I then looked at the power settings (Vista doesn't have a good relationship with recovering from standby mode) but there was no hourly settings. I even rang the supplier of the software on the computer and they didn't have an hourly process.
As it looked like it was an hourly setting, I just did a system restore back to a time prior to the failures occurring and the problem has so far disappeared. My guess at the moment is a virus but unless the problem reappears I'll never know.


Michael Adams said...

I've had that problem with a 2008 server

computer guy said...

Did you manage to locate the problem? Although I have heard of this kind of problems with Windows servers

Chris said...

I'm having the same issue only on the 36 minute after the hour. At ##:36, POOF, an automatic and unwelcome reboot. I'm working with many of the top rate malware guys but so far, nada. Running Avast and it hasn't caught anything. You posted an interesting read - thank you.

Anonymous said...

I'm having a similar problem now with my work PC running Windows Vista.

It's rebooting at 59min past every hour. The last time this PC was used (3 days ago) it was rebooting at 2min past the hour every hour. We suspect the automatic reboot starts exactly an hour after the PC was first swtiched on for the day.

This also happened a few months ago, but resolved after I downloaded the Windows and Virus updates. This time that has not worked. Events Viewer didn't give any leads and Task Scheduler has only a few GoogleUpdateTaskMachine running hourly around the same time which I've just disabled. Will try restoring the PC to a date prior all this if that doesn't work.

Thanks for posting about this. It's so puzzling and frustrating having this in our clinic. You're mid way through a consultation then *poof* all your patient notes are gone.

pst recovery said...

Well the problem depend upon the situation and nature of the problem with the system. I think it is windows files error.