Windows vs. MSN Messenger?

From: Arthur (anonymous_at_discussions.microsoft.com)
Date: 06/30/04 

Date: Tue, 29 Jun 2004 18:14:14 -0700

Where is there info that explains the diff between these
2?
Currently have both and keep getting msgs saying that am
already logged in on another computer. My guess is that
one or the other sees the opposing version logged in and
is spitting out the error msg.
I would like to know which program to disable/delete and
how to do it properly.
Thanx.