Common Issues When Using SIP Devices With Teams

Publisher

Microsoft

URL

https://learn.microsoft.com/en-us/troubleshoot/microsoftteams/phone-system/sip-gateway-issues

Published

2026-05-12

Updated

unknown

Accessed

2026-10-02

HTTP status

200

License

Microsoft Learn content; CC BY 4.0 for docs text per MicrosoftDocs repos, verify before reuse; no-redistribution; short excerpts and locators only

Source notes citing this source

• For failures to make or receive calls on a SIP Gateway device, Microsoft says to check the device is registered, restart it, and test the same call to or from the same remote address in the Teams app. in context
• Microsoft's workaround for the unavailable one-time-code enrolment in GCC is Zero Touch Common Area Phone sign-in, which uses the SIP remote login portal with the CAP account, a region (NOAM, EMEA or APAC) and the device MAC in XX-XX-XX-XX-XX-XX format. in context
• Microsoft's SIP Gateway troubleshooting article has no section on one-way or no audio; its call sections cover only failures to make or receive calls. in context
• After factory-resetting an offboarded phone, Microsoft says to re-enter the regional Teams SIP provisioning URL under Auto Provisioning in the phone's admin menu or web interface, save, and restart the phone. in context
• If a device does not update after a successful sign-in, one cause Microsoft lists is a user from a different tenant who signed in and did not sign out gracefully; that user should sign in and sign out again. in context
• Enrolling SIP devices by dialling *55* plus a one-time verification code is not available in the GCC environment. in context
• When a device cannot register to Teams, Microsoft says to check firewall and proxy blocking of the required endpoints and ports, check whether other SIP devices have the same issue (which may mean the service is unavailable), and restart the device. in context
• If remote sign-in to a device fails, Microsoft says to verify the device was enrolled correctly and to try local sign-in. in context
• When a device signs itself out, Microsoft says to check that SIP Gateway is still enabled for the user and whether settings changed, for example the user's phone number being removed. in context
• A SIP device appears in Teams admin center under Teams devices > SIP devices only after a user has signed in to it at least once, and a signed-out device shows as offline. in context
• When a device cannot onboard, Microsoft says to verify the provisioning server URL begins with HTTP and not HTTPS. in context
• When web app authentication fails during SIP Gateway sign-in, Microsoft says to confirm the credentials by signing in to the Teams app with them and, if Conditional Access is used, to make sure the SIP Gateway IP addresses are excluded. in context

Cite this source record

APA

WarmTransfer. (2026, May 12). Common Issues When Using SIP Devices With Teams. WarmTransfer. https://warmtransfer.net/knowledge/sources/ms-learn-troubleshoot-sip-gateway-issues

BibTeX

@misc{warmtransfer-ms-learn-troubleshoot-sip-gateway-issues,
  title  = {Common Issues When Using SIP Devices With Teams},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/ms-learn-troubleshoot-sip-gateway-issues},
  note   = {Microsoft, accessed 2026-10-02}
}