It's all well and good going back to the old version, and it is your choice, but the problem you will start to get is that you will get pestered by "Please Update To Version 7.0.." or, the MSN servers for that version will be slowly stopped. This is probably why, afaik, versions under 6.0 do not work, as they can't afford to keep all the server up and running, when almost everyone is on the new MSN. This is why they don't still have a download for MSN 6.2 on the main website.
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