BleepingComputer.com: MSN messenger wont install

hey, last time I tried to get on msn messenger, it told me I had to update it in order to login. Ok, no problem, but when I try to update it goes through the entire installation thing, it goes all the way up to 100%, then it rolls back everything (uninstalls it) and gives me this error code: hr:0x80004005. I have tried installing it in both my regular account and as an administrator, my firewall is turned off, its a fresh install of vista, so im pretty sure I have no malware or anything else on it, and it worked just fine under the old version. I can also log on under my XP laptop, and under a msn clone in ubuntu, but I would like to know how to repair this so I can run it in vista. I am running vista ultimate 64 bit. thanks.