Mitel 6867i Administrator's Manual page 273

Reference
To use the lock/unlock softkey or programmable key, see
Softkey on the IP Phone"
CONFIGURING A LOCK/UNLOCK SOFTKEY USING THE MITEL WEB UI
Using the Mitel Web UI, you can configure a softkey on the phone (softkey, programmable key,
expansion module key) to use as a lock/unlock key. In the Mitel Web UI, you assign the function
of the softkey as "Phone Lock".
Use the following procedure to configure a key as a lock/unlock key using the Mitel Web UI.
MITEL WEB UI
1. Click on Operation->Softkeys and XML
or
Click on Operation->Programmable Keys
or
Click on Operation->Expansion Module <N>.
Note: Depending on your phone-model, the key configuration screen displays.
2. Select a key you want to configure for locking/unlocking the phone.
3. In the "Type" field, select Phone Lock from the list of options.
4. Click Save Settings to save your changes.
Using the Configured Lock/Unlock Softkey on the IP Phone
After configuring a key as a lock/unlock key, refer to the following procedure to use the key on
the IP phone.
on page 5-12.
Operational Features
"Using the Configured Lock/Unlock
5-12