Can I throw in some thoughts? From your description of the problem and the fact that you are able to use the programme properly using a different account it sounds as if your User Profile has got corrupted in some way. Although it's going to cause you a lot of work I reckon the only way out of your problem is to delete your own User Account and create a new one. Before you delete you need to create the new account and put it in the Administrator group, log on to this new account and set it up the way you want it. Make sure Messenger works (and all the other things) and then, if you wish, you can delete the old account. A lot of grief I know just to get sounds in Messenger but I don't think there is another way.