Few tricks that you can try by yourself: Fix1: Ensure that the USB cable is safely fitted into the computer and printer. Associate both the computer and printer via a USB cable. Note: The USB port is situated at the rear side of the printer. Fix 2: Follow the procedure below to connect the printer and computer again.  For macOS, ensure that the lock logo is located in the lower-left corner of the Printers & Scanners window.  If the locked icon shows up, hit the icon to unlock. (The password and administrator name are essential to unlock.)  Detach the USB cable from the PC and printer and fit it again. Note: Remember that printer working should not be in progress and be switched off.  Now, switch on the printer. Fix3: Re-install MP Drivers.  Download the latest MP Drivers.  Switch off both the PC and printer.