To migrate from a Webex MPP firmware to a enterprise firmware perform the following steps. If your our phones previously had an enterprise firmware you do not need a migration license when going back to enterprise from MPP firmware.
Download latest firmware from CCO
https://software.cisco.com/download/home/286255327/type/282074288/release/14.3(1)SR2?catid=280789323
Place loads file in local tftp root.
Browse to phone webpage
https://<IP-Address>/admin/advanced
Navigate – Voice > Provisioning > Upgrade Rule
If you have a MAC and need a local TFTP server you can follow these steps to enable the TFTP server:
In terminal
sudo launchctl load -F /System/Library/LaunchDaemons/tftp.plist
sudo launchctl start com.apple.tftpd
sudo chmod -R 777 /private/tftpboot
Use Finder Go to Folder and place the firmware in /private/tftpboot