i spent the last few days trying to work out why Virtualdub wasn't encoding, it was giving me a specific error message but i couldn't find anything helpful on Google, just one forum post, but the user was using a Mac so the suggestions weren't relevant.
The change had only occured in the last few days and i was frustrated, so i decided that a reformat wouldn't do any harm. But i forgot to backup my documents, so i've lost quite a lot of stuff, including my CV, which i really hate writing.
My problem wasn't solved, thinking back the that forum post i realised it was relevant, because it was the same type of error. I thought back to what i had changed a few days ago, it was my Anti-virus, which i had upgraded to the latest version. It turns out Virtualdub think the file it's trying to create is in use because the AV is scanning all the time.
I should set up a blog for this type of thing.