Consider the following scenario:
- Microsoft Skype for Business Server 2015 is integrated with Microsoft Exchange Unified Messaging (UM). Both user A and user B are UM-enabled.
- User A sends user B an email message that contains Japanese characters in the subject.
- User B receives the email message, and then moves the mouse point over user A.
- User B makes a call to user A from the drop-down list next to the phone icon.
- User A doesn't answer the call and receives a missed call notification email message.
This issue occurs because the user notification XML file that's sent by Skype for Business Server is encoded by using US-ASCII instead of UTF8.