Mac doesn't recognize printer/scanner

[Jane221]

My wireless printer/scanner, Photosmart C4780, used to work fine with my Mac, both functions. At some point the scanner stopped working, I think it may have been related to a Mac upgrade? I'm now on Mac OS 10.13.6. The printer still worked, until I started messing with it. I tried uninstalling and reinstalling to get the scanner to work, using the Apple driver as there's no HP driver for this OS, but now both printer and scanner don't work, and the Mac can't find the printer at all. The blue wireless light is on. The printer is very close to the router, same place it's always been. I've been trying all the troubleshooting steps for hours. At some point there was a suggestion to click the minus under System Preferences/PrinterScanner, but after I did that, and then tried to click the plus to add it back, it wasn't showing up on the list at all. I also uninstalled and reinstalled HP Easy Scan and that didn't seem to do anything.

[senan6806]

@Jane221

A warm welcome to HP Support Community!
A steady wireless light typically indicates that the printer is connected to your home WiFi. Performing a network power cycle and then adding a compatible driver may resolve the issue. Here is how to do it:

1.) Turn off your Mac, Printer and Router.

2.) Unplug the power from the back of router, wait for 10 -15 seconds.

3.) Connect the power cable back to router, turn on the router first. Wait till the router to initialize.

4.) Turn on Printer and Mac.

5.) Use the steps available here to update the software on Mac.

6.) Click the Apple menu, click System Preferences, and then click Print & Scan or Printers & Scanners.

7.) Check if your printer name displays in the Printers list, If your printer is listed, click the printer name, click the minus sign to delete the printer.

8.) If you see multiple printer queues for the same printer, remove all extra printers by selecting them one at a time, and then clicking the minus button  at the bottom of the list.

9.) Click the plus sign , click Add Printer or Scanner, click the printer name.

10.) Click the Use or Print Using menu, select the name of your printer in the pop-up menu. Then click Add.

11.) Try to print.

Let me know how it goes!

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