Which service to stop to prevent people from accessing my pc

From: Master (lunteren_at_hotmail.com)
Date: 08/11/03

Date: 11 Aug 2003 07:45:43 -0700

Hi all,

I am at work and logged on to a domain. Since a couple of days someone
has a program with which he/she can access my pc and take it over.
This is very annoying because the person tends to delete my stuff and
send email on behalf of me. Someone told me that there are services
and if I stop some, my pc is not longer open for that programm. Can
anyone tell me which service to stop, before the intruder does more

Thnx in advance