I just had the biggest technical pain that I have had in the past year. I download the update Windows8.1-KB3000850-x64 which is over 700meg.  I have attempted the install from both Windows update and from downloading it from here. It always would proceed fine and then need to reboot the machine. During the reboot it gets to 8% of install then it goes to another screen that states that, “Couldn’t Complete the Updates Undoing Changes.” After it backs out the changes it restarts fine.

Many other people have had problems with this patch. Some of them were able to fix it by running these two commands from an elevated command prompt.

Command Description
SFC.exe /Scannow Description of the System File Checker Tool (Sfc.exe)
DISM.exe /Online /Cleanup-image /Restorehealth Fix Windows corruption errors by using the DISM or System Update Readiness tool

This didn’t fix my system
My system still had the issue – it got to 8% and then failed. Turns out that my system was having issues because I have the Kodak Hero printer driver installed. If you have a Kodak Hero Printer and have this patch issue this is more than a coincidence. This is your problem with this patch, however; removing this printer does not fix the issue.

To Fix this issue
You need to create two folders and then place two files in these folders.
Create these two folders:
– C:\Windows\System32\DriverStore\FileRepository\wiaek002.inf_amd64_57f9361b96ceea4b
– C:\Windows\System32\DriverStore\FileRepository\prnekcl2.inf_amd64_59438dc7ce792b20

Copy these files into each folder created above
– C:\Windows\Inf\wiaek002.inf
– C:\Windows\Inf\prnekcl2.inf

You can cut and paste the commands below to do the work for you.

Execute these commands in an elevated PowerShell or CMD prompt 

mkdir C:\Windows\System32\DriverStore\FileRepository\wiaek002.inf_amd64_57f9361b96ceea4b
copy C:\Windows\Inf\wiaek002.inf C:\Windows\System32\DriverStore\FileRepository\wiaek002.inf_amd64_57f9361b96ceea4b

mkdir C:\Windows\System32\DriverStore\FileRepository\prnekcl2.inf_amd64_59438dc7ce792b20
copy prnekcl2.inf C:\Windows\System32\DriverStore\FileRepository\prnekcl2.inf_amd64_59438dc7ce792b20

All Done Smile

That should take care of it. Run the patch from either the download or Windows update.

– Brian


What to do if that doesn’t fix it?

That should take care of it for you. If that doesn’t take care of it then you will need to start over. Take a look at the logs.

  • C:\Windows\Logs\CBS\CBS log
  • C:\Windows\Logs\DISM\dism log

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