Try removing MSN first by doing this:
First, make sure you have exited MSN messenger and unsinstalled any MSN Messenger related entry from Control Panel (START — > CONTROL PANEL — > ADD OR REMOVE PROGRAMS). Then, START — > RUN the following command:
RunDll32 advpack.dll,LaunchINFSection %windir%\inf\msmsgs.inf,BLC.Remove
Then, try installing an older version from here:
OldVersion.com