|Apparently the 'program' was downloaded in order to play a rather dubios video. When the video was played in VLC there was music but no sound so he ran the installation file for the RPEX codec.|
This has installed RPEX.EXE on my computer. I don't know what it does and it wouldn't allow me to delete it. However it seems that it has now gone so I guess mbam and CC finally did the trick.
I am NOT convinced that this is a genuine codec and would advise caution at the very least.
Thanks for the help anyway.