HP OfficeJet Pro 6978 Automatic Duplexing Unit Driver Issue

[ZGIRRL]

HP OfficeJet Pro 6978/Windows 10

UPDATE:  After searching quite a bit, i found a similar issue on here, where i'd tried the solution before.  i read through it again and this time, went into the settings for the printer and downloaded Windows Update drivers.  There was a PCL-3 updated driver available (which i had chosen not to use previously).  I selected this driver and i am now printing double-sided again!  I have not tried scanning yet, but since it never broke, i'm going to guess it will be fine.  Super happy because it just doesn't seem right for HP to not provide support for an out of warranty printer that doesn't get heavy use, but stops working due to drivers!!  I'm also an Instant Ink subscriber!

A few months back, after an Office 10 update (or so i thought, my printer stopped printing double sided.  It's been printing and scanning perfectly for years (since Oct 2017).  I thought it was due to a Windows 10 update, but now i'm not so sure.  I have fixed the issue by deleting and reinstalling the printer.  There is not a newer driver from the April 2018 driver, but it seems to work only if i use the original file i downloaded.  I found that it would work for a bit and then revert back to saying the ADU was not installed.  Just now, i performed the steps again and the ADU was installed (via Printer Properties).  I went to Word (i have Office 365) and went to print the document which was the reason for doing the fix again).  The driver grayed out the option to double-side print.  I went back into Printer Properties and the ADU option was returned back to Not Installed.  This was fine for 3 years - zero problems.  Any ideas?  

[sandytechy20]

@ZGIRRL

Welcome to the HP support community.

Did you uninstall the printer driver from the root level before installing the new driver?

If not follow the below steps:-

Perform root level uninstallation to remove all the printer related software's.

• In Windows, search for and open Programs and Features.
• Select your HP printer.
• Select Uninstall.
• In Windows, search for and open Devices and Printers.
• In the Devices and Printers window look for your HP Printer. If you see it listed, right-click on it and choose "Delete" or "Remove Device.”
• Open up the run command with the "Windows Key + R" key combo.
• Type printui.exe /s and click OK.
• Click on Drivers tab.
• Look for HP Printer driver. If you see it click on it and click Remove at the bottom.
• Select OK.
• Remove all instances of the same.
• Select Apply and OK on the Print Server Properties windows.
• Close Devices and Printers. 
• Restart the PC again.

Download and install printer HP Smart app

Click here to download.

Update the printer firmware

Here are the steps:- Click here

I hope that helps.

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

Cheers.

[ZGIRRL]

THANKS so much!  i actually did this multiple tilmes and fixed it this way a handful of times.  Eventually, this workaround stopped working.   I apologize for not  updating the post.  I came her to do a reply and didn't see how to do it (and didn't think to just edit the post - diuh!!)  

I ALWAYS get updates to update the "critical" firmware update but the process always says i'm already up to date.  i ended up fixing the problem (without it recurring immediately) by having Windows install the PCL driver.  The problem was really weird in that the first time, completely uninstalling and installing via the download from HP fixed it for a while, the next time, the same thing helped, then it got to where i could do nothing to fix it until i uninstalled everything and installed via Windows.  

THANK YOU so much for your response!  i was getting pretty frustrated and i kept trying different things (i''m a technical support person - though for specific packages and not end user pc's 🙂 )  

[sandytechy20]

@ZGIRRL

Good to know that issue is resolved.

Feel free to contact us in the future if you need any assistance.

Cheers.