Change the drop down marked to no scan - otherwise it will invoke a quick scan with Avast as you have it resident
Does that file have a manufacturer under properties ? I feel it may be becoming a bit sensative with the heuristics
Do you have a dell or HP as the MBR is non standard due to the recovery partition, this is not evident under Vista/7 as a different recovery method is used
I have an HP but there is no recovery partition because I completely wiped the HD and installed XP Pro from another disk. I didn't use the HP recovery disks. I did however install all of the HP drivers including HP Quick Play which makes a 1gb partition at the end of the drive for the files needed to boot into Quick Play without fully booting Windows. I can push the DVD or Quick Play buttons on my keyboard when the machine is completely shut down and play a DVD without, as I said, fully booting into Windows. Maybe this has caused the non standard MBR you mention.
The file does have ATI Technologies as the manufacturer and it's described as - ATI Radeon WindowsNT Miniport Driver. It's a file that's present in all Radeon driver packages. When I navigate to the file and do a right click scan with Avast, it says it's clean. That's kind of strange , isn't it?