follow this link and read through it (it is a bit long) then try the cures that you are comfortable with.
Doing the following seems most successful but there are other fixes suggested.
Do note that you will want to download the full SP2 (the standalone download which is Method 3) from this link -
http://support.microsoft.com/kb/935791
Just before running it open an elevated command prompt and run these two commands:
net localgroup Administrators LocalService /add
nd
net localgroup administrators NetworkService /ADD
In case you don't know, here is how to initiate an elevated command prompt:
Click Start, click All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.
Now select the Servic Pack executable you just downloaded and right click it and RUN AS Administrator
I've read the many posts by people who have had blue screens of death after installing Service Pack 1, but I tried installing it anyway because a program I wanted wouldn't install without it. But I figured I could just install Service Pack 2 and that would fix things.
Not so.
The installation of Service Pack 1 went well, but afterward I began getting the blue screen crashes. Then Service Pack 2 wouldn't install. (I got a message stating: Error: E_NOINTERFACE (0x80004002). I can get my data off, but using it for any length of time causes my system to crash.
Can anyone help? There doesn't seem to be a way to back out of this horrendous patch.

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