1st try this

Click “Start”

Then Click “Run”

Copy and Paste this ” regsvr32 MSXML3.dll ”

Click “OK”

You should see a dialog box stating that the operation has suceeded.

Then open Messenger again and sign in.

If this doesn’t work then try to clear your DNS cache by:

Click “Start” then “Run” and type “cmd.exe”

Then type “ipconfig /flushdns”. You should get a message stating that the cache has been cleared.

if thats not working try this

edit the registry and find for this key ‘UseWUServer’ if the value is ‘1’ ). I changed it to ‘0’, rebooted, and Run Windows Update