When I try to run Oleview I get an error saying that DllRegisterServer failed for IViewer.dll (sorry I wanted to post a screenshot but I can't until I get 10 reputation =p)
Oleview will run but like the msg says, you can't look at interfaces which is exactly what I want to do.
I found my iviewer.dll and ran regsvr32 on it just fine. So I'm not sure whats up.
You only need to run it the first time as admin. Make sure you open a tlb file though, so it registers IVIEWERS.DLL as COM server into the registry. After that you can run it as a normal user. This is explained in the Windows SDK readme, by the way.