Source note · Setting up Extension Mobility in Unified CM
With Multiple Logins Not Allowed, a user can be logged in to only one device; a login attempt on a second device fails and the phone shows error code 25.
Checked 2026-09-30
The login attempts to the second device fails and the phone displays the error code "25" (Multi-Login Not Allowed).
- Vendor
- Cisco
- Product
- Unified Communications Manager
- Subsystem
- Extension Mobility
- Deployment
- on-premises
- Region
- not restricted
- Release range
- Release 15 and SUs
- Checked
- 2026-09-30
Sources
- Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Extension Mobility — Cisco Systems · tier 2 current vendor documentation · Extension Mobility Service Parameters table, Multiple Login Behavior; Troubleshooting, Error 25 User Logged in Elsewhere
Cite this note
APA
WarmTransfer. (2026, September 30). Setting up Extension Mobility in Unified CM: source note cucm-extension-mobility-setup-multi-login-error-25. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-extension-mobility-setup-multi-login-error-25
BibTeX
@misc{warmtransfer-claim-cucm-extension-mobility-setup-multi-login-error-25,
title = {Setting up Extension Mobility in Unified CM: source note cucm-extension-mobility-setup-multi-login-error-25},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-extension-mobility-setup-multi-login-error-25},
note = {Source note cucm-extension-mobility-setup-multi-login-error-25, checked 2026-09-30}
}