Resolve Webex Calling MPP Phones Fail to Re-register after Factory Reset Due to Original Onboarding Method Differences

Issue

Cisco 8845 and 9871 MPP phones did not automatically re-register to Webex Calling after a factory reset and instead remain at the activation code screen. The affected phones require deletion and rebuilding in Control Hub so an activation code can be manually entered for registration to complete. Most phones on the same network and VLAN register normally after factory reset without requiring manual intervention.

The issue is impacting phone provisioning and registration workflows, requiring additional administrative overhead to restore phone functionality after factory resets.

Environment

• Cisco 8845 MPP phones

• Cisco 9871 MPP phones

• Webex Calling deployment

• Legacy DHCP option 150 entries from previous CUCM deployment deleted

• Approximately 4500 phones in environment with only select phones affected

Resolution

The issue was resolved by changing the phone onboarding method from activation code to MAC address onboarding in Control Hub.

This limitation is addressed in "Factory reset a Webex Calling phone" link provided:

If the phone was originally onboarded using its MAC address, it reconnects to Webex Calling. If the phone was onboarded using an activation code, it requires a new activation code or needs to be onboarded using its MAC address to reconnect to Webex Calling.

Identify Affected Phones

Determine the onboarding method used for phones by examining the status.xml file in the Problem Report Tool (PRT):

• GDS-Acquired: Indicates GDS (activation code) onboarding.

• Acquired: Indicates EDOS (MAC address) onboarding via activate.cisco.com.

Re-add Phones Using MAC Address Method

Step 1: Delete the affected phone from Control Hub.

Step 2: Re-add the phone using MAC address onboarding instead of activation code method.

Step 3: Perform factory reset on the phone.

Step 4: Verify the phone registers automatically without requiring activation code entry.

Validation

After implementing MAC address onboarding, the phones successfully re-register after factory reset without remaining at the activation code screen. The phones now follow the EDOS provisioning process with "Cert-based-EDOS" onboarding flow instead of requiring manual activation code entry.

Cause

The root cause is the difference in onboarding methods between affected and working phones. Phones originally onboarded using activation codes (GDS method) show provisioning method status "Open" and remain at the activation code screen after factory reset, requiring manual activation code entry through the GDS activation process.

In contrast, phones originally onboarded using MAC addresses show provisioning method status "Acquired" and proceed with automatic Cert-based-EDOS onboarding, allowing registration without manual intervention.

Legacy DHCP option 150 entries from a previous CUCM deployment contributed to provisioning complications but were not the primary cause of the activation code requirement.

Related Content

• Factory reset a Webex Calling phone

• Troubleshoot MPP Phone in Webex Calling for Provisioning Issues

• Cisco Technical Support & Downloads

Revision History

Revision	Publish Date	Comments
1.0	09-Nov-2026	Initial Release