Symptoms
When non-English-based characters are used in the Custom footer text filed of Microsoft Lync 2013 (Skype for Business) meetings, some of these characters aren't getting properly displayed in the Outlook meeting invitation.
Resolution
To fix this issue, install the September 6, 2016, update (KB3118281) for Lync 2013 (Skype for Business). Note Lync 2013 was upgraded to Skype for Business in April 2015.