I don't know if this will work but if there's nothing else you can do then try this. First unistall (or atleast try to). Ok then run a program like system mechanic which has a registry scanner. Run it and remove any invalid registries that it shows. You can use any other good registry scanner but i cant help you about which one is free and good cause i use system mechanic
. Newayz after doin this reg scan reboot your pc and then download this file. Its "Msn Msg 7 Beta" from "Official Windows Site" (Dunno where you got it from)
http://g.msn.com/7MEEN_US/EN/INSTALL_MSN_MESSENGER_DL.EXE
Then install that newly downloaded file and i guess it should work. If it doesn't then man your luck is bad. Wait till the full (non beta) version of msg 7 comes out
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