morphing file types

[stb1swat]

I found this infected file, so to speak, and I've been trying to shred it using Spybot shredder. Everytime I "shred" it, it morphs into a new file name and file type. It was originally in my system32 folder.
Here are some of the file types its been changing too, and its never used the same one twice.
.wcd
.rrr
.tqy
.lfg
.bso
.riz
.uai
.zon
.vvy

How can I get rid of it?

 

[Osiris]

http://www.techist.com/forums/f51/spyware-removal-guide-osiris-updated-11-13-2008-a-165828/