mess.be
As reported by many Messers on the forum and via e-mail, the .NET Messenger Service is being a pain in the dérrière the last few days. Some of you received messages from contacts who appeared offline, while others were unable to send messages to specific contacts. Presently, the service is even temporarily unavailable ("You may be unable to sign in. Please try again later. Last Update: 12/6/2005 10:28:00 AM Pacific Time"). Please be patient while Microsoft tries to glue the pieces together again.
Might explain it