There's a "Inetpub" folder under C: I somehow forgot how I got it into my computer. Is it related to UPnP or any kinda protocol? so I try to delete it directly but the system says they can't find that on my HD.
Maybe you can share with us what you did to get this folder. If something created a folder you can bet it created things in other places as well.
This folder is created when you install the IIS web server. To remove the web server and folder, go to Add/Remove Programs, and click on Add/Remove Windows Components. You should see the IIS server listed in there.
by the way...I found out there are some worms, Worm_fujacks.al for instance, affected folders under Inetpub. Is this a bug related to UPnP in windows XP?
I'd suggest uninstalling the web server first....then run a virus scan on the system. Turn off System Restore before you do.