This is a particularly weird conundrum and I probably made a lot of stupid mistakes so bear with me.
I tried uninstalling the scrobbling software from my computer (I have Windows 7) and for some reason it wouldn't let me because even after I had closed down the client, I was notified that the uninstalling process couldn't go through because the client was still running.
After I tried that about five times, I decided to just go ahead and delete it directly, since uninstalling didn't work at all. Unfortunately, this left me with some files left over that I still cannot delete since they are apparently still running in Last.fm.
I can't reinstall the software that I downloaded because Last.fm is still running, according to the system.
Trouble uninstalling/reinstalling