You can lock the handset keypad to prevent all keys from being accidentally pressed. 

To lock the keypad via the handset:

  1. Long press Pound (#)when the handset is idle until the LCD screen prompts: Keypad Locked, Press and hold ‘#’ to unlock!
  2. The keypad is locked and the Lock icon appears on the status line.
  3. You can still answer or reject incoming calls as usual. You can also end the answered call by pressing the End Call key.

To unlock the keypad via the handset:

  1. Long press Pound (#) again until the LCD screen prompts Keypad Unlocked. The keypad is unlocked and the Lock icon disappears from the idle screen.

Note: If the keypad is locked, the emergency numbers can be dialed out. You must enter the emergency number continuously. To place emergency calls, you should configure the emergency numbers in advance.

Read the Yealink W52 Cordless Phone User Guide for more information.