It is only on OS X since Mavericks upgrade.
The client works with the same credentials perfectly fine on Windows and iOS devices. We have read something from Technet to try and login with invalid credentials upon first try but this makes no difference, we still receive the same error. In the advanced settings, we have a manual configuration with the internal and external server names set to: :443 If the problem continues, please contact your support team. Please verity your logon credentials and try again. We have downloaded the latest client with updates and still no joy.
We have recently upgraded to Mac OS X Mavericks and ever since, Lync for Mac 2011 will not connect to the Office 365 servers.
