HP4787D6 (HP OfficeJet Pro 8620) Driver will not install

[DlsGal]

Hi, I used to be able to print from my laptop  (Win10 x64 bit) with my HP All-in-one 8625 printer and then one day it stopped printing.  When I went to Devices and Printers, it showed the installed printer (HP4787D6  - HP OfficeJet Pro 8620), but said the "Driver was unavailable".   

I deleted the printer and the associated software, and tried to add the printer back to my network, but said "Driver is Unavailable" both under the Add Printer section and also under my list of printers.  When installing the driver from the HP website, during the "Network Check" it finds the printer on my network.  When I select it and and click Next, at the "Network Printer Installation" screen, it fails and says "the printer was unable to be installed over the network".

Things I have done:

Turned off my McAfee firewall.

Turned off the router, printer, computer and then turned back on in same order.

Used HP Scan & Print Doctor tool to no avail.

Removed the HP printer and software several times and tried to reinstall wirelessly and am not successful. 

Note: I am able to print from another laptop and from mobile phones.  This isn't the first time to happen, my work issued laptop stopped printing all of a sudden.  I thought it was maybe new security features my workplace implemented, but luckily when I received the new work laptop and connected and printed just fine.  So does another new laptop I just purchased.  

Please help.  I have spent HOURS trying to troubleshoot.  My printer is out of warranty and really don't want to have to buy another one since it is only 2 years old and has no operational issues.  (It's a great printer!)

Thanks for any help you can provide. 

[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

[Gary_P_Frey]

The same thing is happening with me

[RockstarComp]

This Worked! Thank you. Windows 10 64Bit with Officejet 8525 Printer