HP Printer Flashing Lights

[HappyEagle75]

I have an HP OfficeJet Pro 8720 which is connected both wirelessly and via USB. It works fine and operates normally when the computer is on. However, when the computer goes to sleep or shuts down, the printer lights all start flashing rapidly including the display (which is blank but solid white). When I turn the computer back on the printer stays in the flashing mode and will not work until I press the start button. The printer then starts normally and works fine as long as the computer is on. HP Print/Scan Doctor finds no issues with the printer. How do I fix this issue?

[sandytechy20]

@HappyEagle75

Welcome to the HP support community.

I understand that your printer is not reconnecting to the printer after restarting the computer and the printer display goes blank.

I am glad to assist you and fix this issue.

Are you getting any error messages?

Meanwhile:- 

Perform a power reset to set the printer to last know good configuration

1. Turn on the printer, if it is not already on.
2. Wait until the printer is idle and silent before you continue.
3. With the printer turned on, disconnect the power cord from the rear of the printer.
4. Wait at least 30 seconds.
5. Plug back the power cable straight to a wall outlet and printer without any surge protector.
6. Turn on the printer.

Update the printer firmware to install the latest updates

Here are the steps:- Click here

Let me know how it goes.

To thank me for my efforts to help you, please mark my post as an accepted solution so that it benefits several others.

Cheers.