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Call waiting query

Occasional Visitor

Call waiting query

Hi Support,


We have a number of ip 331 phones linked to lync 2010 server.  We have found an issue where by if a caller is currently busy on the phone and another person tries to ring that call, call waiting will kick in.  What we want is should this occur recieve an engaged tone rather then the other phone ringing.


Looking into the admin guide it mentions disabling call waiting by updating the sip-interop.cfg file and setting the callwaiting.enable to 0.  If we make this change will this actually disable the call waiting functionality through out, ie should will a caller calling a busy phone recieve an engaged tone?


For information we have phones running UCS and bootrom





Message 1 of 3
Polycom Employee & Community Manager

Re: Call waiting query

Hello Marc,

welcome to the Polycom Community.

The only way to prevent multiple calls into the phone is to set it to only allow one call per line.


Usually you would set a maximum calls to arrive on your Phone on the SIP server end, i.e. LYNC.


Any changes made to the configuration on the phone would only disable the audible tone.


Please be aware of the following when utilizing UCS 4.1.0 or later:

The use of Polycom UC Software versions 4.1.X (“Software”) requires the purchase of a separate Software license for every device that will use the Software in a Lync environment. You may not install, access, or use the Software in a Lync environment on more devices than are listed on your license until additional licenses have been purchased and authorized by Polycom. These licenses should be purchased from the same company from which you purchased the devices. You may operate devices against a Lync server for trial purposes for up to 30 days without purchasing a license. Use of the Software is subject to the terms and conditions of the End User License Agreement.

Polycom reserves the right to audit your deployment to verify that you have sufficient licenses to match the number of devices being used.

Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.

Best Regards

Steffen Baier

Polycom Global Services

The title Polycom Employee & Community Manager is a community setting and does not reflect my role. I am just a simple volunteer in the community like everybody else. All posts and words are my own & do not represent the views of Employer.


Notice: This community forum is not an official Poly support resource, thus responses from Poly employees, partners, and customers alike are best-effort in attempts to share learned knowledge. If you need immediate and/or official assistance please open a service ticket through your proper support channels.
Please also ensure you always check the VoIP , Video Endpoint , Skype for Business , PSTN or RPM FAQ's
Message 2 of 3
Occasional Visitor

Re: Call waiting query

Thanks Steffen for your reply,


Unfortunatly I have already tried setting a phone to allow one call per line but this doesn't work.  The person on a cally will not see another call coming in, however the caller when ringing a busy phone will ring for around 15 seconds and then get a busy tone which isn't what we want.


I believe the only option is to use busy on busy.


Thanks for clarifying this for me.





Message 3 of 3