OfficeJet Pro 6975 was working fine, then things went wonky

[embren]

I purchased and installed the 6975 a few weeks ago.  It was working great.  I could print, I could scan from the computer, and more importantly, I could start the scan from the printer itself.  All of a sudden, scanning stopped working all together but printing was still working.  This printer is connected to my wireless network as is my HP laptop.

I did all of the usual things - powered off, unplugged, reset the wireless connection on the printer.  I rebooted the laptop.  Nothing worked.  I re-installed the software via internet download.  I was then able to start and successfully complete a scan from the printer to the laptop.  Yay!

However, in the Printers & Scanners section in Settings, it says "Driver is unavailable" for this printer.  

In addition, I used to be able to run the HP Printer Assistant.  Now when I run 

"C:\Program Files\HP\HP OfficeJet Pro 6970\Bin\HP OfficeJet Pro 6970.exe" -Start UDCDevicePage, Device Setup starts.

But on my 4650 printer, the HP Printer Assistant runs when I run this (which appears to be the same except for the path):

"C:\Program Files\HP\HP OfficeJet 4650 series\Bin\HP OfficeJet 4650 series.exe" -Start UDCDevicePage

If I run HP Print and Scan Doctor, it says that the full software solution isn't installed.  I had repeated the initial setup again as I said above.

[ShlomiL]

Hi,
Please follow the steps below to resolve such an error:

**Be aware that if you have other printers installed on your PC, those will need to be reinstalled too once completing these steps.

1. Uninstall the HP Software from your PC.
2. Backup your registry prior making any registry changes:
     https://support.hp.com/in-en/document/c03485724
3. Update your registry using the Reg file below (that will change some printer related policies for your PC):
     https://www.dropbox.com/s/avbv56zdgwv7600/kernel.reg?dl=1
4. Right click the Start menu and select Run.
     Type Services.msc and press OK.
     Locate and stop the Print Spooler service
5. Browse to c:\Windows\System32\spool\drivers.
     Rename W32X86 to W32x86.old
     Rename x64 to x64.old
     Note: if any of these folders fail to rename reboot your PC and then Continue following the steps starting from Step 4...
6. Restart your computer.
7. Reinstall the HP Software and check for any difference

Please let me know the results,
Shlomi

[embren · Accepted solution]

So far, so good!  Thank you very much!