If you want to be a bit patient you could probably get Windows Live Messenger and wait a little while until Messenger Plus Live! is released...otherwise uninstall both MSN 7.5 and WL 5.1 completely including deleting any left over files and then trying to do the process again
Could you possibly also have Messenger Plus installed from a time you have used in the past??
Or has messenger plus ever worked in the past for you?
annnndddd is the a error message that appears when you start the Messenger Plus Installation?
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