Deleting trust files from phones is a last resort: the bulk ITL reset from Unified CM should be tried before touching phones individually, because a manual deletion must be done at each phone.

inferred · Checked 2026-09-24

Vendor
Cisco
Product
Unified Communications Manager
Subsystem
ITL
Deployment
on-premises
Region
not restricted
Release range
Release 15 and SUs
Status
inferred
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Troubleshooting Cisco IP phone registration: source note cisco-phone-registration-troubleshooting-itl-first. WarmTransfer. https://warmtransfer.net/knowledge/claims/cisco-phone-registration-troubleshooting-itl-first

BibTeX

@misc{warmtransfer-claim-cisco-phone-registration-troubleshooting-itl-first,
  title  = {Troubleshooting Cisco IP phone registration: source note cisco-phone-registration-troubleshooting-itl-first},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cisco-phone-registration-troubleshooting-itl-first},
  note   = {Source note cisco-phone-registration-troubleshooting-itl-first, checked 2026-09-24}
}

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