Contact faults

Hello,

I have recently downloaded windows live messenger like so many of you
I am having trouble with the contact list it wont let me see them
I added them and then a message comes saying that they dont have the program when they do and i think it's because it was a newer version of my old msn i downloaded giving by a friend and i deleted my other msn now i am having problems and im thinking cause i deleted if im right someone please tell me? that would help me understand msn more
Probably it won't show my contacts so thats another problem if anyone can help it would be greatly appreciated

Can anyone help me with this problem/s?