Symptoms
When this issue occurs, you receive the following message:
Call could not be put on hold
This issue occurs in the following scenarios:-
Media bypass for the Enterprise Voice infrastructure is enabled.
-
The call is routed to a public switched telephone network (PSTN) through version 8.x of Cisco Unified Communications Manager (CUCM) or an earlier version of CUCM.
Resolution
To resolve this issue, install the October 2014 update for Lync 2013 (KB2889929).
More Information
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.