Can't sign in with MS Lync

Solution 1:

Solved this today. I'm not sure what finally solved it but this is what I did ...

  1. Install the latest Mountain Lion Update which was published today

  2. Completely uninstall Lync as described here http://support.microsoft.com/kb/2691870 Reinstall Lync + do the Lync update to v14.0.6

  3. Change my password - as my old one contained a German special character.