5. Printer

• About authentication failed.
• Open an app from an unidentified developer

About authentication failed.

If you pasted the IPP password, there is a possibility the password includes some extra characters like a space.

• If you pasted the password, make sure it does not include a space.
• Example:

  　   passwd　
  　^^^      ^^
  

Open an app from an unidentified developer

• When clicked a pkg file, a message as "can't be opened because it is from an unidentified developer." is indicated.
  
• It's right-clicked and Open is chosen from the menu.
  
• from an unidentified developer. Are you sure you want to open it? The message to say so is indicated, so Open is clicked.