If it is A-patch, just run A-patch, select restore backups and press next.
Then you can install the patch again
without checking
'remove contacts personal message'.
If you have deleted the patch you can download it from
http://apatch.tk/
If you don't have any backups, go to control panel, add/remove programs, go to MSN Messenger 7 and click change. This will renistall MSN Messenger. Then you can run the patch.