welcome to the Polycom Community.
The community's Skype for Business FAQ contains this post here:
Jan 17, 2017 Question:How can I troubleshoot simple Skype for Business, LYNC or Office365 issues?
Resolution: Have a look => here <=
Also the VoIP FAQ can be utilized
Jan 19, 2012 Question: How to troubleshoot Polycom VoIP related Issues?
Resolution: Please check => here <=
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
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