The application has failed to start because its side-by-side configuration is incorect

I just installed, uninstalled and re-installed Windows Live Messenger and the only way I can get into it is via hotmail, but then it only gives me a drop-down menu with only my on-line contacts showing, and not the rectangular window with my contact list, both on and off-line and many other capabilities.  So I tried going in via WLMsgr by going to start, and finding it in the list of programs in the main page.  When I did that I received the pop-up msg "The application has failed to start because its side-by-side configuration is incorrect.  Please see the application event log for more detail."

Ok, so....where do I find the app. event log and then what do I do with it?  My OS is Windows Vista Business.  Then, how do I reconfigure side-by-side? And finally, if I can rectify this problem/error will I be able to access WLMsgr, create a short-cut and have it the rectangular window with several tabs and options?

I used MSN Msgr quite some time ago, when it was easier (and I'm not a novice ;) ).

Thanks for any help you can give me.