Applies To

Call2Teams - Partners


Call2Teams now offers the ability to manually set an extension number for users, in the Call2Teams portal on Partners 

whose customers are not using the Teams sync module and where the users have ext= set in Microsoft Teams as part of their phone number:

This is so that user telephone numbers from Microsoft tenants can be mapped to the appropriate Teams profile, if the customer uses extension numbers but does not use the Call2Teams Sync feature.

We have added this as an option for Partners whose customers may be affected by a change that Microsoft made to Direct Routing, where they have set extension numbers for their users but are using the manual Sync feature. 

Microsoft will deploy the Direct Routing change in July 2023, and we have pushed this update to Call2Teams to ensure that affected customer users can still receive calls.


It is possible that customers may see a 404 Not Found error when attempting to contact users affected by this Microsoft Direct Routing change.

Error CodeDescriptionDescriptionAdvice
404Non-sync missing extension number

Microsoft Teams Phone Number routing logic change, specifically matching for users with extensions.

The extension field must be set by the partner on the user account in the appropriate template.


To set the ext= number in the Identity header. 

1. As an administrator, log into the Call2Teams admin portal and navigate to the Users tab.

2. Click the padlock icon next to the Extension box, to the right of the user’s phone number.  This will unlock the extension number field for that user.

3. Manually enter the correct extension number for the user.
Note: By default, Call2Teams treats numbers shorter than six digits as extension numbers.

4. Repeat as necessary for any affected users.

See Also

How to View, Add or Remove Teams, PBX, or Trunk Services


Users experiencing any issues should raise a support desk ticket by the usual means.