Follow the instructions below:

TD-4420DN/TD-4520DN
 

1. Turn off the printer.
2. Press and hold the Feed button ( ) and the Power button ( ) for about three seconds.
   All LED indicators flash in red.
3. While holding down the Power button ( ), press the Feed button ( ) once.
   The Power LED lights in red.
4. Release the Power button ( ).
   All LED indicators flash in red four times, and then light in red.
   All the network settings will be reset.

TD-4550DNWB
 

1. Press Menu.
2. Press or to select the following:
   1. Select [Administration]. Press OK.
   2. Select [Reset]. Press OK.
   3. Select [Network Reset]. Press OK.
3. Press  or to select [Reset]. Press OK.
   All the network settings will be reset.