Blue Screen Problem

[mark59]

I have a problem with my laptop PC. I need advice on this problem.

Computer: Acer Aspire 5920
OS: Windows Vista Home Premium Service Pack 2

At the time I encountered this problem I was running Windows Update. The message, in full, that has come up on my computer's blue screen is as follows:

"A problem has been detected and Windows has been shut down to prevent damage to your computer.

DRIVER_IRQL_NOT_LESS_OR_EQUAL

If this is the first time you've seen this stop error screen, restart your computer. If this screen appears again, follow these steps:

Check to make sure any new hardware or software is properly installed. If this is a new installation, ask your hardware or software manufacturer for any Windows updates you might need.

If problems continue, disable or remove any newly installed hardware or software. Disable BIOS memory options such as caching or shadowing. If you need to use Safe Mode to remove or disable components, restart your computer, press F8 to select Advanced Startup Options, and then select Safe Mode.

Technical information:

***STOP: 0x000000D1 (0x00650043, 0x00000002, 0x00000000, 0x 83641129)

*** iastor.sys - Address 83641129 base at 83601000, Datestamp 46ff320c"

This is the first time this blue screen has appeared. I have not installed any new hardware or new software.