Used Samsung Phones Unlocked here. Earlier a friend called me while working at a client location and needed to know how to configure the VLAN on a Cisco 7940 IP Phone. I always forget the different ways to unlock different phones and wasn’t having an easy time locating the method on Google but finally did locate how to unlock the the Cisco 7940. Below is information on how to unlock the Cisco 7940 phones. Unlock Cisco 7940 Phone Configuration: By default the configuration on a Cisco 7940 phone is going to be locked. Once you get into a sub section such as Network Configuration you can unlock the settings by clicking **# on the 7940’s keypad. How To Unlock Broken Iphone 6 more. You should see the lock go from locked to unlocked next to each configuration item. Cisco 7940 Tips: • VLAN: It is possible you will need to configure the VLAN to work on your network.