Yeah it gave me a list of possible reasons why it couldn't install, eg: Wrong CD in drive. But I wasn't trying to install anything in the first place!

Starman: Norton automatically deleted the file.

Someone on the uTorrent forums has basically told me that WFP is oversensitive and will warn at too many changes, even done by Windows update. And basically that although this warns of system instability; if a majorly important file was damaged/replaced, it has either been done well, otherwise my PC would not function at all.
...Makes sence to me.