Note: This is an old thread!
Cannot Sign into MSN 7.5? READ HERE!
and read some of the latest threads under
MSN/Windows Live Messenger subforum
There, some methods were written to sign-in on 7.5. When you could signin again, copy paste all notes like Patchou said. Then signin Windows Live Messenger and again copy paste notes to Windows Live Messenger's contact windows. But you mustn't have uninstalled MP! v.3, because I think when MP! is uninstalled, all data which it keeps are deleted permanently.
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