A scan by Norton Security Suite discovered sbnudh.dll in my system32 folder. It never did anything to it, apart from altering me to the fact that it is some sort of adware. So I attempted to delete it manually, but it wont delete. I found an entry in the registry for sbnudh.dll and successfully deleted it, but it still remains in system32 folder.
I am also getting a red pop-up saying that my PC is infected with malware and to click for details on how to sort it - this leads to a web page for SpyFalcon antispyware.