so need some advice and thoughts

I logged onto msn today and chatting away suddenly this person who i dont know have no clue how they got my contact or on my list starts messaging me now can anyone tell me is there a way of finding out who this actually is and how they got on my msn ? as well as i am wondering whether this a prank .. although not a funny one as it was offensive .. let me know any thoughts if anyone has this happen before

Someone may have invited youinto a conversation then left.

did you get any " <username> has left the conversation" messages?

thanks dazmatic and puniksem
they not only have a username but also i have my setting on requesting permission before becoming part of my list it was as if i had lets say given someone my email and said ur friends can add me to their list

but i havent done that

There's an option to right click in the systray, and when you choose "send an instant message..." you can send 'to an email' which probably means that this is easily possible if this person has your email. I can't test it not knowing people whos emails I don't have, but that could be the case.

Also, is there a chance they're a deleted contact?

Be sure to check the "Only people on my allow list can see my status and send me messages" feature in the privacy section of MSN options.... This will make it so people that aren't on your allow list (or contact list) will be able to comment you... If this doesn't work... just block the person.