From what i see now is that the popup (blank screen) is most likely from the handwriting plugin (you have the correct version of Plus! for your version of MSN), telling you it wasn't installed correctly (ink redist). You can get ink redist
here, make sure you choose "for all" and not "just for you" whilst installing that. Also see
Ink/handwriting, all you need to know....
Asfor it being blank that is most likely caused by the other things i mentioned (IE not updated, ActiveX and/or Java not being installed).
Edit: Still looking forward to hearing from you if i was correct and if it's solved or not...
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