1. Always restart the computer and the printer.
If it's wireless MAKE SURE THE WIRELESS LIGHT ON THE PRINTER IS LIT UP IT's NORMALLY BLUE.

2. Make sure your printer and computer are on the same network.
You may have one to three different networks. Joe's home network or work (wired), Joe's 2.5 ghz, Joe's 5 ghz, Joe's 5.2 ghz.
If the computer is WIRED it should work with the printer on any of the wireless network.
If the computer is on WIRELESS MAKE IT'S ON THE SAME WIRELESS AS THE PRINTER.
The printer is on Joe's 2.5 ghz the computer MUST BE ON Joe's 2.5 ghz.
To NOT get HACKED as easy the printer and your computer should be wired! EVERYTHING WIRELESS CAN BE HACKED!

3. If you have changed networks on the computer or the printer to make them match?
You need to restart both the printer and the computer if either one was changed.

4. HP printer support videos
HP's website:
https://supportvideos.ext.hp.com/category/videos/printers-and-all-in-ones

HP's youtube (google-tube) channel:
https://www.youtube.com/user/HPPrinterSupport

Any questions please ask here.