I've got Windows XP and in the last few days, it's been extremely slow (i.e. taking 5 seconds to insert a row in Excel). I opened up my Task Manager and see a process called "agent.exe" taking up tons of my CPU (30% with gusts up to 99%). I've got no idea where this program came from. I ran McAfee and it didn't come up as a virus.

Anyone have any ideas on what it is and how to get rid of it?

agent.exe is a process belonging to Avira Internet Security Suite which protects your computer against Internet-bound threats such as spyware and trojans which can be distributed through e-mail or attack directly to the computer allowing unauthorized access to your computer. This program is important for the stable and secure running of your computer and should not be terminated.

Note: Note: agent.exe could also be also a process associated with the Forte Agent Newsgroup reader, this could also be a is non-essential process to the running of the system, but should not be terminated unless suspected to be causing problems.

Determining whether agent.exe is a virus or a legitimate Windows process depends on the directory location it executes or runs from.