Assume that you install a version of Microsoft Lync for Mac 2011. Then, you install a later version of Lync for Mac 2011. In this situation, an additional icon for Lync for Mac 2011 is created in the Dock.
Note A new docked icon will be created for each new installation.
To resolve this issue, install the following cumulative update:
2909662 Description of the Microsoft Lync for Mac 2011 14.0.7 update
Article ID: 2909671 - Last Review: 12 Dec 2013 - Revision: 1