Troubleshooting Webex Calling phones that will not activate or onboard

See also

Sources

1. 1
   An activation code generated in Control Hub for a Webex Calling device is 16 digits long.

   Generate an activation code for a device · Procedure steps: 'A 16-digit activation code is shown' · Checked 2026-10-02
2. 2
   After generating an activation code an admin can copy, email or print it, and the email can go to someone other than the device owner.

   Generate an activation code for a device · Final procedure step (Copy, Email or Print) · Checked 2026-10-02
3. 3
   The MPP administration guide states that activation code onboarding requires firmware release 11.2(3)MSR1 or later.disputed

   Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · Activation Code Onboarding section, prerequisites · Checked 2026-10-02
4. 4
   The Webex Calling device management article states that multiplatform phones must run firmware 11.3.1 SR2 or later for users to enter an activation code.disputed

   Configure and manage Webex Calling devices · Add and assign devices in bulk · Checked 2026-10-02
5. 5
   Activation code onboarding requires the phone profile rule set to gds:// and activation.webex.com allowed through the firewall.

   Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · Activation Code Onboarding section · Checked 2026-10-02
6. 6
   An admin generates a user's device activation code in Control Hub under Users, selecting the user, then Devices, then Add Device.

   Generate an activation code for a device · Procedure for a user's device · Checked 2026-10-02
7. 7
   For a shared device, the activation code is generated in Control Hub under Workspaces, selecting the workspace and using Add Device.

   Generate an activation code for a device · Procedure for a workspace device · Checked 2026-10-02
8. 8
   The device-management article lists a subset of devices that register with an activation code, including 6800 series audio phones, the 9800 series, the 9821 wireless phone and the 8875 video phone.

   Configure and manage Webex Calling devices · Add and assign devices in bulk, activation-code device list · Checked 2026-10-02
9. 9
   A Control Hub activation code for an MPP phone is valid for 30 days.

   Generate an activation code for a device · Activation code validity note (MPP phones versus Room devices) · Checked 2026-10-02
10. 10
    A Webex endpoint activation code is one-time use, so a code that was already consumed returns an invalid activation code error.

    I Can't Activate My Cisco Webex Endpoint · Cause section: activation code used / one time use only · Checked 2026-10-02
11. 11
    A Control Hub activation code for a Webex Room device is valid for 7 days, which is shorter than the MPP phone validity.

    Generate an activation code for a device · Activation code validity note (MPP phones versus Room devices) · Checked 2026-10-02
12. 12
    On firmware 12.0.3 or later the activation code screen appears at out-of-box first start or after a factory reset.

    Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · Activation Code Onboarding section · Checked 2026-10-02
13. 13
    For an analog telephone adapter all network settings such as VLAN and IP addressing must be configured before activation because they cannot be changed afterwards.

    Generate an activation code for a device · ATA note in the procedure · Checked 2026-10-02
14. 14
    After an MPP phone registers successfully to the Webex cloud a cloud symbol appears on the phone screen.

    Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · Activation Code Onboarding section, Webex note · Checked 2026-10-02
15. 15
    Deleting a phone in Control Hub automatically factory resets it when the phone runs firmware 12.0.3 or later.

    Factory reset a Webex Calling phone · Closing notes, automatic reset on delete · Checked 2026-10-02
16. 16
    A phone being reassigned to another user or workspace must first be deleted in Control Hub.

    Factory reset a Webex Calling phone · Closing notes, reassignment · Checked 2026-10-02
17. 17
    New phones use activate.cisco.com for zero-touch provisioning, so it must be reachable for onboarding.

    Port Reference Information for Webex Calling · Domains and URLs for Webex Calling services table, activate.cisco.com row · Checked 2026-10-02
18. 18
    MPP phones older than release 12.0.3 must be allowed to reach sudirenewal.cisco.com on port 80 to renew their manufacturer installed certificate.

    Port Reference Information for Webex Calling · Domains and URLs for Webex Calling services table, sudirenewal.cisco.com row · Checked 2026-10-02
19. 19
    cloudupgrader.webex.com serves firmware upgrades and secure onboarding of devices, and binaries.webex.com serves firmware and locale downloads.

    Port Reference Information for Webex Calling · Domains and URLs for Webex Calling services table, cloudupgrader.webex.com and binaries.webex.com rows · Checked 2026-10-02
20. 20
    Phones on firmware released earlier than 11.2(1) continue to use webapps.cisco.com instead of activate.cisco.com.

    Port Reference Information for Webex Calling · Domains and URLs for Webex Calling services table, activate.cisco.com row · Checked 2026-10-02
21. 21
    The Cloud Upgrader requires cloudupgrader.webex.com, activate.cisco.com, activation.webex.com and *.wbx2.com allowed on 443, with cloudupgrader also on 6970.

    Cisco Cloud Upgrader (Enterprise to MPP firmware migration for Webex Calling) · Requirements, firewall allowlist · Checked 2026-10-02
22. 22
    For bulk DHCP staging, the Cloud Upgrader sets DHCP option 150 to 3.14.211.49 or option 66 to cloudupgrader.webex.com, and option 160 to the cloudupgrader EDOS $PN/$MA.cfg URL.

    Cisco Cloud Upgrader (Enterprise to MPP firmware migration for Webex Calling) · Bulk DHCP method, DHCP configuration for EDOS onboarding · Checked 2026-10-02
23. 23
    The Control Hub migration article tells admins to install or upgrade the enterprise phone firmware to 14.1 or later before migrating.

    Migrate enterprise phone to Webex Calling phone firmware · Prerequisites section · Checked 2026-10-02
24. 24
    Cloud Upgrader migration of CUCM-registered phones fails if an ITL or CTL trust list is installed; it is removed under Admin Settings, Reset Settings, Security Settings.

    Cisco Cloud Upgrader (Enterprise to MPP firmware migration for Webex Calling) · Bulk CUCM method notes · Checked 2026-10-02
25. 25
    When an eligible enterprise phone is added for migration, a migration license is generated automatically and applied when the MPP load requests its onboarding configuration.

    Migrate enterprise phone to Webex Calling phone firmware · Introductory notes on migration · Checked 2026-10-02
26. 26
    A migrated phone that shows an activation code prompt asking to provide the migration license indicates the migration licenses must be checked in the Control Hub migration tool.

    Cisco Cloud Upgrader (Enterprise to MPP firmware migration for Webex Calling) · Troubleshooting notes, registration · Checked 2026-10-02
27. 27
    Activation code onboarding is not supported when migrating a phone from enterprise firmware to MPP firmware for Webex Calling.

    Migrate enterprise phone to Webex Calling phone firmware · Introductory notes on migration · Checked 2026-10-02
28. 28
    If a migrated phone is stuck showing Configuration check in progress, Cisco's recovery step is to power cycle it.

    Migrate enterprise phone to Webex Calling phone firmware · Notes in the complete-migration procedure · Checked 2026-10-02
29. 29
    A TFTP Timeout during Cloud Upgrader migration means the phone cannot reach the Cloud Upgrader or download firmware; check firewall requirements and the Phone Load setting.

    Cisco Cloud Upgrader (Enterprise to MPP firmware migration for Webex Calling) · Troubleshooting notes, network failures · Checked 2026-10-02
30. 30
    Wireless-connected phones lose their wireless network settings when the MPP firmware is applied and must be reconnected by Ethernet afterwards.

    Migrate enterprise phone to Webex Calling phone firmware · Notes in the complete-migration procedure · Checked 2026-10-02
31. 31
    Factory resetting an activation-code-onboarded phone as a troubleshooting step consumes its onboarding, so the admin should have a fresh code or MAC onboarding ready before telling a user to reset.inferred

    Factory reset a Webex Calling phone · Closing notes after the per-family sections · Checked 2026-10-02
32. 32
    A site that staged enterprise-to-MPP migration with DHCP options 150/66/160, or that still serves CUCM TFTP options, will likely keep diverting factory-reset MPP phones away from Webex Calling activation until those options are removed.inferred

    Troubleshoot MPP Phone in WxC for Provision and Registration · DHCP configuration section, combined with the provisioning order in cisco-mpp-desk-ag-provisioning · Checked 2026-10-02
33. 33
    Meraki appliances acting as DHCP servers advertise their own IP as the NTP server in DHCP option 42 without hosting a reachable NTP service, which can stop Webex phones registering.

    Unable to Register a Webex Room Device or Webex Call IP Phone to Webex · Cause section, Meraki item · Checked 2026-10-02
34. 34
    From a user's device page in Control Hub an admin can create a new activation code for the device where applicable, alongside reboot and delete actions.

    Configure and manage Webex Calling devices · Manage a device for a user · Checked 2026-10-02
35. 35
    A firewall or router blocking UDP 123 prevents time sync and is a listed cause of Webex phones failing to register, with symptoms including a wrong (2015) date and certificate errors.

    Unable to Register a Webex Room Device or Webex Call IP Phone to Webex · Symptom and Cause sections · Checked 2026-10-02
36. 36
    Cisco's Meraki workaround is to resolve 0.tandberg.pool.ntp.org, set a custom DHCP option 42 to the returned IP and reboot the device.

    Unable to Register a Webex Room Device or Webex Call IP Phone to Webex · Resolution section, Meraki steps · Checked 2026-10-02
37. 37
    Webex Calling devices need UDP port 123 for NTP time synchronisation.

    Port Reference Information for Webex Calling · Device time synchronization (NTP) row in the port tables · Checked 2026-10-02
38. 38
    Device configuration, firmware upgrades and secure onboarding with the 16-digit activation code (GDS) use TCP ports 443, 6970 and 80.

    Port Reference Information for Webex Calling · IP Subnets for Webex Calling services table, device configuration and firmware management row · Checked 2026-10-02
39. 39
    A 9800 or 8875 PhoneOS phone joining Webex Calling is registered by choosing Cisco cloud service then Register when asked for a call service.

    Register your PhoneOS device (9800 Series/8875 phones) · Call service selection steps · Checked 2026-10-02
40. 40
    The PhoneOS 5.0(1) release notes state that the enhanced Webex Calling activation code onboarding process requires PhoneOS 4.0 or later.

    Release Notes for Cisco PhoneOS Phones 9800 and 8875 · PhoneOS 5.0(1) section, Prerequisites · Checked 2026-10-02
41. 41
    If an automatic onboarding step fails on a PhoneOS phone, the phone prompts for an activation code, a call service choice, or both.

    Register your PhoneOS device (9800 Series/8875 phones) · Onboarding procedure, failure note · Checked 2026-10-02
42. 42
    NFC onboarding is supported on the 9841, 9851, 9861 and 9871 but not on the 9811 or the NR (non-radio) variants.

    Register your PhoneOS device (9800 Series/8875 phones) · NFC onboarding section · Checked 2026-10-02
43. 43
    When DHCP provisioning does not succeed, the MPP phone queries the Cisco EDOS remote customization server with its MAC address and model.

    Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · Remote customization (EDOS RC) section · Checked 2026-10-02
44. 44
    An MPP phone tries auto-provisioning mechanisms in the order DHCP, DNS SRV, EDOS, then GDS activation code onboarding or EDOS device activation.

    Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Provisioning · DNS SRV provisioning section, ordered mechanism list · Checked 2026-10-02
45. 45
    When a reassigned phone is to be onboarded by MAC address, entering #000 on the Activation Code screen re-onboards it to Webex Calling and provisions it to the new user or workspace.

    Configure and manage Webex Calling devices · Reassigning an existing phone to another user or device · Checked 2026-10-02
46. 46
    Before a Webex Calling phone is reassigned to another user or workspace it must be factory reset, using Device administration then Factory Reset on the phone.

    Configure and manage Webex Calling devices · Reassigning an existing phone to another user or device · Checked 2026-10-02
47. 47
    The alternative 0 then 369# keypad reset works only on the 8841, 8845, 8851, 8861 and 8865 at hardware version 15 or later.

    Factory reset a Webex Calling phone · 7800 and 8800 Series, Method 2 · Checked 2026-10-02
48. 48
    After a factory reset, a phone that was onboarded by activation code needs a new activation code or must be onboarded by its MAC address.

    Factory reset a Webex Calling phone · Closing notes after the per-family sections · Checked 2026-10-02
49. 49
    A 6800, 7800, 8800 or 8875 phone can be factory reset by unplugging it for 5 seconds, holding # while reconnecting power, then pressing 123456789*0# in sequence.

    Factory reset a Webex Calling phone · Per-family sections, keystroke sequence · Checked 2026-10-02
50. 50
    After a factory reset, a phone that was onboarded by MAC address reconnects to Webex Calling without a new code.

    Factory reset a Webex Calling phone · Closing notes after the per-family sections · Checked 2026-10-02
51. 51
    On a 7800 or 8800 phone in Webex Calling the menu reset is Settings, then Factory reset; on a 6800 it is Settings, Device administration, Factory reset.

    Factory reset a Webex Calling phone · 6800 Series and 7800 and 8800 Series, Settings menu method · Checked 2026-10-02
52. 52
    An MPP phone can be factory reset from its web page by browsing to http://<phone IP>/admin/factory-reset and confirming.

    Cisco IP Desk Phone with Multiplatform Firmware (MPP) Administration Guide - Maintenance · Factory Reset the Phone from Phone Web Page · Checked 2026-10-02
53. 53
    After provisioning, a healthy MPP registration sends an unauthenticated REGISTER, receives 401 Unauthorized with a digest challenge, then re-registers with credentials and receives 200 OK.

    Troubleshoot MPP Phone in WxC for Provision and Registration · SIP registration process section · Checked 2026-10-02
54. 54
    A TFTP server or DHCP options 66, 150, 159 or 160 handed to an MPP phone prevent it from provisioning from Webex Calling servers, because the phone requests its profile from that TFTP server instead.

    Troubleshoot MPP Phone in WxC for Provision and Registration · DHCP configuration section · Checked 2026-10-02
55. 55
    A log line reading Couldn't resolve host for the activation host shows that DNS resolution of the provisioning URL failed.

    Troubleshoot MPP Phone in WxC for Provision and Registration · DNS resolution troubleshooting section · Checked 2026-10-02
56. 56
    In Cisco TAC's MPP provisioning walk-through, the phone's first provisioning request goes to activate.cisco.com.

    Troubleshoot MPP Phone in WxC for Provision and Registration · Provisioning flow section · Checked 2026-10-02
57. 57
    When a DHCP TFTP conflict is found, remove the TFTP server and options 66, 150, 159 and 160 from the phone's DHCP scope, then factory reset the phone and restart provisioning.

    Troubleshoot MPP Phone in WxC for Provision and Registration · Remediation steps following the DHCP section · Checked 2026-10-02
58. 58
    A PRT log is downloaded from the phone web GUI at https://<phone IP>/ under Info, Debug Info, Download PRT log; the phone IP is shown under Settings, Status, Network Status.

    Troubleshoot MPP Phone in WxC for Provision and Registration · PRT logs analysis and device web UI access sections · Checked 2026-10-02
59. 59
    To detect a DHCP TFTP conflict, search the PRT logcat file for DHCP-tftpsvr1 or DHCP-tftpsvr2.

    Troubleshoot MPP Phone in WxC for Provision and Registration · PRT logs analysis section · Checked 2026-10-02

Documents

Cite this page

WarmTransfer. (2026, October 2). Troubleshooting Webex Calling phones that will not activate or onboard. WarmTransfer. https://warmtransfer.net/knowledge/webex-calling-phone-activation-troubleshooting

@misc{warmtransfer-webex-calling-phone-activation-troubleshooting,
  title  = {Troubleshooting Webex Calling phones that will not activate or onboard},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/webex-calling-phone-activation-troubleshooting},
  note   = {Verified 2026-10-02}
}