spyware traces?

Recently yahoo messenger refuses to allow me login claiming I am logged on to another pc or device. I did some testing and A-Squared claimed I had IMMONITOR pointing at my yahoo install exe file. It also claimed I had traces of Find Out Now Spy in the registry pointing to a file called DWSPY32.dll
My question is, is there anyway of determining if either of those exist and the source of the install?
Thank you