Printed pages blank if sent by computer but works as scan or under glass, ink adequate

[MsPatty]

HP office jet all in one printer, office jet pro 6978, wireless set up.

[Nal_NR]

Hi @MsPatty,

Welcome to the HP Support Community. 

I'd be happy to help you! 

I understand that you are facing issues with the printer printing blank pages. 

To be able to assist you better please let me know the Operating System installed on your computer

Are you able to make Photocopies?

Meantime please try these steps

Let's start with a Printer Reset

(1) Turn the printer on, 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) Unplug the power cord from the wall outlet.
(5) Wait at least 60 seconds.
(6) Plug the power cord back into the wall outlet.
 NOTE: HP recommends connecting the printer power cord directly to the wall outlet.
(7) Reconnect the power cord to the rear of the printer.
(8) Turn on the printer, if it does not automatically turn on.

The printer might go through a warm-up period. The printer lights might flash, and the carriage might move.
Wait until the warm-up period finishes and your printer is idle and silent before you proceed

Then Print a Quality Diagnostic page and let me know if that prints

Load plain white paper in the input tray.

From the home screen on the printer control panel, swipe down to open the Dashboard, and then touch the Setup icon .

Swipe up on the display, touch Reports, and then touch Print Quality Report.

A Print Quality Diagnostic Page prints.

Figure : Example of the Print Quality Diagnostic Page

1. 

Please perform these steps at your convenience and keep me posted.

If the test print-prints blank, 

Ensure the cartridges are well vented and installed

Examine the vent area above the HP logo on the top of the ink cartridge.

If the ink cartridge still has the orange pull-tab attached, pull to remove it.

If the vent is clogged, use a straight pin to gently remove excess adhesive from the vent.

1.  

1. Clogged vent

With a straight pin, gently remove excess adhesive from the vent

Unclogged vent

Turn the ink cartridge so that the cartridge contacts face downward, and then match the label color with the color dot on the carriage.

Next align the printhead using the printer control panel.

On the printer control panel, swipe down to open the Dashboard, and then touch the Setup icon .

Swipe up on the display, and then touch Printer Maintenance.

Touch Clean Printhead, and then touch Continue.

A test page prints.

Examine the test page.

If the print quality is unacceptable, touch Clean Again to continue the next level of cleaning. Repeat these steps for the third cleaning stage, if necessary.

   NOTE: If the printhead is badly clogged, it might require another cleaning cycle. If so, wait 30 minutes before you perform all three levels of cleaning again.

If the print quality is acceptable, touch Done

Let me know if this helps

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