When I start up my pc (vista) it warns me that Windows defender has stopped a program at start up, this program is part of a video codec I downloaded and is to update the codecs, it isn't essential and to stop windows defender warning me each time, I tried to take it out of the start up procedure, however when I try, I end up in the defender screen and all the options for removing or allowing startup programs are greyed out. Any ideas?

I only had it as it was part of the bundle, but if it is that rubbish, out it goes tonight with the rubbish.

out of interest, what is the program/codec?   I don't use Windows Defender as I've previously found it to be akin to an ashtray on a motorbike (and annoying, to boot), but is there not an option to permanently unblock that program?