Symptoms
This issue occurs when you run a Microsoft SIP Processing Language (MSPL) script in Skype for Business Server 2015 and the script tries to read from an external flat file but can't do so because of insufficient permissions or a conflict with another process that's writing to the file at the same time.
Resolution
To fix this issue, install the June 2016 cumulative update 6.0.9319.259for Skype for Business Server 2015, Front End server and Edge server.
