Assume that you create a meeting in Microsoft Skype for Business 2015 (Lync 2013). Then, you put texts at a whiteboard and save it as a PNG or an XPS file. In this situation, the whiteboard doesn't include all the texts in the page.
This issue occurs because there is an incorrect computation of the size of the PNG file required to save all the annotations.
To fix this issue, install the December 6, 2016, update (KB3127976) for Skype for Business 2015 (Lync 2013).
Note Lync 2013 was upgraded to Skype for Business in April 2015.