Hello,
the Messenger service is currently having problems with contact presence information. The problem is known and should solve as soon as the Windows Live team has repaired the Presence service. You can find more information at
http://windowslivehelp.com/.
quote:
The Windows Live Messenger service is currently experiencing issues. Some or all of your contacts might appear offline after you sign in. Our Messenger Operations team are aware of the problem and are currently working to resolve the issue as quickly as possible.
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