Unlock CTL and ITL Files
To unlock the CTL and ITL files from the Security Configuration menu, perform these steps:
Press **# to unlock options on the overall setting menu of the Cisco Unified IP Phone.
Select Trust List > CTL or ITL file depending on which file is installed in your phone.
Note If both CTL and ITL files are installed in your phone, you can choose either option.
Step 3 Press Unlock to unlock Trust List files on the phone. The CTL or ITL files, if installed on your phone, will be unlocked together.
Note When you press Unlock, the softkey changes to Lock. If you decide not to change the TFTP server option, press Lock to lock the CTL file.