2014-09-16 - News from zyron.c64.org
I had some computer problems recently and thought I'd share the solution here, in case others run into the same problem.

It all started one Sunday morning. When I turned on my PC, Windows XP would no longer boot. I got a blue screen with the following error message:

DRIVER_IRQL_NOT_LESS_OR_EQUAL
*** STOP: 0x000000D1
*** SCSIPORT.SYS

I could not understand what had caused this since I had made no changes to my system the day before.

Booting into Safe Mode worked though, and after quite some time investigating I found the cause;

I was using the Bitdefender antivirus, and the day before I had turned off its real-time protection since it slowed down my system, and never turned it back on before powering down my computer.
This was what caused the error, the realtime protection being disabled!

So, while in Safe Mode I simply uninstalled Bitdefender and after that my system booted normally again.