How to find out which application is connected to which process?

Hey, im new, and not good at solving computer problems.
You see, in the C:/Windows/system32/xxyywuSm.dll

its a malicous virus that is a monitoring program and ive tried alot of means to try to delete it.
I tried using security task manager, Safe mode manual deletion, norton anti virus quarantine, Vundofix, and attempting to end processes and then delete it.
But it all links to saying, “this program is being run by a process or person. Shut down process to delete it”
Problem is, i was on safe mode, and i cant still get rid of it.
Im in dire need of help, if anyone has any suggestions?
(and i also tried using the Service Process identifier by Greg Shultz)