while communicating with a freind a box pops up and invites me to upgrade messenger so i do. while insalling it says clos all aplications of messenger, I dident! it finish, now I have no audio, and problems loging on to msn, and messenger, and also have two messenger  applications on my computer, when I log on with one it tells me im logging on from a differant computer, im not what you would call a coputer whiz by any means, but love my computer.please can you help fix my problem.