We’ve had several calls from users and customers lately, complaining about their Outlook contacts details missing from Lync 2013 all of a sudden.
The common ground for all users is that they’re using Lync 2013 with the March 2014 update (2863908) and Outlook 2010.
Upon removal of this update – the issue is resolved.
We are experiencing a similar issue, incoming calls on Lync now showing DDI instead of Display name on notification toast. Tested a call while signed into Lync 2010 and 2013 simultaneously, 2010 showed display name and Pic as expected whereas 2013 only detected the DDI