[Y!M] Yahoo Messenger Lockup

[rksnj67]

I installed the latest version of Messenger (8.1 I think). I've had 
nothing but trouble. When I log on, it locks up my computer. When 
someone sends me a request to join my friends list, it doesn't work. 
I've never had any problems with earlier versions of Messenger. 
Unfortunately, I can't find any older versions. Any help with my 
problem would be appreciated!