do you save a log file of your AV programs?

it's a long list...open that and look for anything that resembles MS update in the path...

if that is included, more than likely your AV has recognized that as an "intruder"

you can delete that or move that to the "safe" zone..

it might also be in your anti-spy softwares...

if all else fails, uninstall your AV/Anti-spy completely include removing them from your registry

then, re-install them...(there are other ways but this is what I'd do first)