To potentially resolve the Lync/Skype picture issue please follow the instruction below and advise of the results.
1. Exit Lync and ensure that it is not running by
- At the top of the Lync/Skype main window, click the availability menu under your name, and then click Sign Out.
- In the notification area of the taskbar, right-click the Lync/Skype icon, and then click Exit.
2. Delete the "Photo" folder in this location "C:\Users\your username\AppData\Local\Microsoft\Office\16.0\Lync\email@example.com\"
3. Open Lync again and It can take up to 2 hours to pull the photo back in.