When you want to save your contact list in a file to use in another account, do the following:
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[*]In your account containing the contacts you want, go to
Contacts > Save Instant Messaging contacts and save the file somewhere you can remember it.
[*]Now, log off in Messenger and sign in with your new account
[*]Once you're signed in, go to
Contacts > Import Instant Messaging Contacts... and browse to your saved file. Click Open and you're contacts will be added to your new account!
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As you see, you even don't need Plus! for this. You only need Messenger Plus! if you want to export your Plus! settings to another computer.
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