Microsoft states that for inbound Direct Routing calls the phone number in the Request-URI must contain a plus sign.
Checked 2026-10-02
Currently The phone number must contain a plus sign (+) as shown in the following example.
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- Inbound call processing
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Teams Phone System Direct Routing: SIP protocol — Microsoft · tier 2 current vendor documentation · Section 'Detailed requirements for Contact header and Request-URI' > 'Request-URI'
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting SIP 404 Not Found and 484 Address Incomplete call failures: source note sip-404-484-troubleshooting-teams-ruri-plus. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-404-484-troubleshooting-teams-ruri-plus
BibTeX
@misc{warmtransfer-claim-sip-404-484-troubleshooting-teams-ruri-plus,
title = {Troubleshooting SIP 404 Not Found and 484 Address Incomplete call failures: source note sip-404-484-troubleshooting-teams-ruri-plus},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-404-484-troubleshooting-teams-ruri-plus},
note = {Source note sip-404-484-troubleshooting-teams-ruri-plus, checked 2026-10-02}
}