Assume that you use multiple monitors with different DPI settings. When you drag the Microsoft Lync 2013 (Skype for Business) client or window from one monitor to another, the user interface (UI) in the client or window doesn't scale correctly. It's either too small or too big.
Note This issue doesn't occur when you move other Microsoft Office applications between monitors, such as Microsoft Outlook, Microsoft Word, and Microsoft OneNote. These applications can scale the text and window size correctly.
To fix this issue, install the November 1, 2016, update (KB3127934) for Lync 2013 (Skype for Business).
Note Lync 2013 was upgraded to Skype for Business in April 2015.