Sounds like the problem I have with WLM 2012:

The same errormessage (code 800CCC0E) keeps popping up, telling me that the server has disconnected, although there aren´t any other problems with my internet connection. I tried to repair from Controlpanel/Live Essentials, but it didn´ t help.

Also the messages I have read, often returns to "unread" mode.

I guess you can make a total backup of your contents (mails and contacts), and then uninstall WLM and then install it all over again. But is that really the only solution??