When I start my Dell computer (Dimension E510), I GET a message that WINDOWS XP is shutting down because of a problem file, AT12Dvag, which is causing the device driver to "get stuck in an infinite loop." I am allowed to operate in safe mode, but not NORMAL mode. Restarting the computer doesn't help. Any thoughts? Thanks.

PligwiglBoot to safe mode, uninstall the ATI driver, reboot. Then download and install the latest driver for your video CARD (obtain the driver from the ATI website, not from Windows Update).Drivers & Downloads for Dimension 5150/E510Oops - thanks CC.
pligwigl - please disregard my suggestion to get the driver from ATI. Laptop drivers should always be obtained from the website of the laptop manufacturer. I missed that we were dealing with a laptop. Please follow the link in the post above this one.Alan, I have a PC not a laptop. Should I therefore follow the advice on your first post. Thanks.

PligwiglOkay, back to the original thought. Yes, get the latest driver from the ATI website. Also, please do not start new threads for this topic. Just post here - I'll see it. I merged your post into this thread.Thanks. I didn't at first see how to reply without a new post, but I do now.Thanks for the link, Computer_Commando.Alan, my computer has 8 ati2dvag files. Seven have the suffix dll and are listed as Application Extensions. The one exception has no suffix, video\addon\B_25699. It is 131 KB and is listed as DL_Files. Is this the file I need to uninstall?

PligwiglYou delete by going to ADD / REMOVE programs in XP or Programs & Features in Vista or W7. DO NOT delete the files "manually"