Microsoft response code 510532 with SIP 403 ('No trunk config was found' or 'RuntimeApi trunk config not found for customer') means Direct Routing found no trunk configuration for the call. Microsoft says to check that calls come from the correct SBC FQDN for the tenant, that the Contact header FQDN is registered to the tenant, and that the gateway configuration is correct.

Checked 2026-09-25

Vendor
Microsoft
Product
Microsoft Teams Phone Direct Routing
Subsystem
sip-response-codes
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Troubleshooting Teams Direct Routing: source note teams-direct-routing-troubleshooting-403-510532. WarmTransfer. https://warmtransfer.net/knowledge/claims/teams-direct-routing-troubleshooting-403-510532

BibTeX

@misc{warmtransfer-claim-teams-direct-routing-troubleshooting-403-510532,
  title  = {Troubleshooting Teams Direct Routing: source note teams-direct-routing-troubleshooting-403-510532},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/teams-direct-routing-troubleshooting-403-510532},
  note   = {Source note teams-direct-routing-troubleshooting-403-510532, checked 2026-09-25}
}

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