Comdial DX-120 Mike's PBX Tips

Changing the Password for Vertical or Comdial DX-120 Extensions

How to Reset the Password on Comdial or Vertical Phones (DX-120)

Comdial first introduced the DX-120. Vertical who bought Comdial continued to manufacture the DX-120 with the Vertical name which can be seen on the telephones, as well as the PBX KSU. These instructions are good for both PBXs.

Vertical/Comdial DX-120 manuals: DX-120 Telephone and System Manuals

For refurbished renewed telephones from a trusted vendor; Comdial DX120 7261 Desk Phone

Changing Time on a Comdial DX-120

Note: The default password for all extensions is 0000 (four zeros) except for extension 101 which is 9999.
  • First from the extension press FEATURE 97.
  • On your telephone display you will see PSWD:_ with soft-key functions of bksp (backspace), show, and chg (change).
  • Next input your current password, which should be the default password 0000, if it has not been previously changed.
  • Your display will then show LOCK PHONE with the softkey options of pswd (password), yes, and no.
  • Next Press pswd and the display will change to N PSWD:_ with the softkey options of bksp (backspace), save, and chg (change).
  • Input your new password and then press Save.

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