With HP Pavilion laptops, users have often noticed that when the Num lock is ON, letters are not being displayed. Nothing changes either when performing Fn + Num lock and Fn + F11. This problem only occurs when Num lock is kept ON; letters are displayed correctly at all other times. To type numbers instead of letters, the user just needs to hold the Function (Fn) key whilst typing. To solve this keyboard issue, one just needs to press the Fn + Num lock or Fn + Shift + Num lock keys, depending upon the model of the laptop being used.
If you are writing numbers instead of letters when you're pressing the keyboard of your laptop and you have to hold down the Function key (Fn) to write normally. This is due most of the times to the fact that the digital lock is activated. To solve this, simply press: Fn+Numlk or depending on the model, press the button or Fn+Shift+Numlk. This will solve your problem