Messenger-- Can't Open It

Hey guys, I am here with a very dumb but at the same time very uncomfortable issue. I use Windows XP, so I have one MSN Messenger that already comes with the system. But this version is old and standard, it doesn't have many applications as the newer ones. So I downloaded the 9.0 version and used it 'till the day it suddenly stopped working and I couldn't even open it anymore. The window that appeared was that one "MSN Messenger found a problem and needs to be closed, report to Microdoft if you want to, bhla bhla bhla", which obviously doesn't help one bit. So I unistalled it and installed again-- and guess what? It STILL doesn't work, no matter how many times I do it. I even tried to unistall the older MSN, but then I found that I couldn't. :(

So...ANY ideas? :)