A software problem masquerades as a hardware problem

I was asked to repair a Windows Vista computer that would consistently fail with a “blue screen of death” within minutes of starting. This is usually a symptom of a memory problem, but memtest86 (run from a DOS boot CD-ROM) failed to find a problem. Sometimes an overheated CPU will cause this problem, but the CPU seemed to be in firm thermal contact with its heatsink and both the CPU and power supply cooling fans were spinning. Sometimes a bad disk sector in the middle of the system kernel will cause this symptom, but testing the disk revealed no bad sectors. I suspected a weak power supply, but the computer ran fine with Windows in Safe Mode. I finally concluded that one or more 32-bit Windows drivers (which don’t load in Safe Mode) or anything else in Windows that doesn’t load in Safe Mode must be the culprit.

While in Safe Mode, I noticed that someone had installed a half-dozen unusual anti-malware and driver management utilities, plus a large assortment of toolbars. I tried to uninstall them, but most refused to uninstall in Safe Mode. Still in Safe Mode, I ran services.msc and disabled services that were associated with these dubious programs.

Interrupt Process
Source: Stephen Charles Thompson (anon_lynx)
When restarted, the computer ran fine. Those utilities must have been fighting over the same interrupt. So now it was just a matter of removing the superfluous junk that had been installed, updating Windows, and installing Microsoft Security Essentials.

What caused the problem?
When prompted to install a supposed piece of security software, novices often reason “If some is good, more must be better”. With security software, this is not true.


Caveat: Disabling the wrong service in services.msc can cause serious problems. Proceed with caution. Be prepared to reinstall Windows or at least to restore to an earlier restore point if something breaks.

Visit my website: http://russbellew.com
© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

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2 thoughts on “A software problem masquerades as a hardware problem”

  1. I recently had a similar problem on one of my PCs. I had gotten several different error messages when it went to BSOD, which made me question whether it could be a hardware problem. I restored to an earlier point and also updated some of the Dell drivers. It seems to be running fine so far….

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    1. Nice work! I had tried Windows’ “restore system” without success. One thing I didn’t do was update the BIOS. Sometimes a newer BIOS will resolve driver problems. Since an aborted BIOS update can brick a system, though, I update a BIOS only if the installed BIOS is hopelessly out of date (or I’m hopelessly desparate).

      Like

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