Cannot sign in to a desk phone using Teams SIP Gateway

Regular Contributor

Hi all,


I'm attempting to sign in to a Polycom CCX VVX 411 desk phone I have onboarded to the Teams SIP Gateway by following the instructions here. As far as I can tell, the device has been configured correctly; it's got the Teams background image and when I press the Sign In button, it displays the sign in URL and pair code.


When I visit the URL, enter the pair code, and sign in with my credentials, the web page says that I have successfully signed in. However, nothing happens on the phone. I've made multiple attempts from a couple different phones over the past few days.


I've got a ticket open with Microsoft 365 Support, which is going about as well as you would expect. Is it just me, or are others having this issue as well?


Edit: I mixed up the model name.

5 Replies
Hello Ryan, I do not see the CCX 411 in the compatible phones list
Did you successfully use a CCX against SIP Gateway in the past?
Hi Andres, thanks for replying. I mixed up the model name; I meant VVX 411, not CCX.

Am I getting no replies because it's working fine for everyone else, or is nobody else using this feature? :)

best response confirmed by Ryan Steele (Regular Contributor)
I finally got connected with a helpful Microsoft 365 support rep and it turns out the problem was that the "SIP devices can be used for calls" setting was not enabled on the Calling policy assigned to the user.

My fault, to be sure; that being said, it would be helpful if there were some kind of error message during the web sign in process if the setting is disabled rather than being told "You have successfully signed in". May my misfortune serve as a warning to others.
Hello Ryan,
Great news then...
That step is indeed in the procedure

I agree that a meaningful error message would be better