Use DEP in Safe mode (Press f8 when your comp boots up) select Safe Mode.
Wait till it boots up. Right click on “My Computer” go to properties.
Select Advanced > Look at Performance, Click on settings

>Click on Data Execution Prevention > Click on “Turn on DEP for all programs and services except those i select”

Click on “Add”
And Locate the Executable Program “.exe” by following the guidelines above where it tells the location of exe’s

Restart your computer, and let it boot up normally.
Now the virus should get a message “when a program crashes you get a error reporter thing” Guess what? The virus gets the messege in it’s face!

Now you are able to access Regedit and any other option that was blocked. Except Task manager.

This is the achille’s Heel of that annoying virus. DEP just owns any virus that trys to mess with you. The wonders of microsoft.

I hope this helps because the last thing to do if all fails is to reformat the computer and install a fresh copy of windows.

I tried this for XP Prop, it should work with all windows having DEP. (which all of them should have)