Greetings! I’ve managed to make a modified Intel HD620 and UHD620 driver for windows 8.1x64. My only remaining issue was the certificate. I followed a very good tutorial, I made my own certificate and applied it to the .cat files. I installed the certificate and ran the setup.exe.
Everything seems to work just fine; but if I check the driver from the Device Manager it says that it is not digitally signed. Even tho the .cat files were signed, I’m pretty sure!
If anyone has any idea, how to fix this, or what should i do, please let me know!
Thanks!
EDIT by Fernando: Thread moved and title customized
Please read the “Welcome” box of the Forum’s Portal site. Your request needs a meaningful title and should be put into the “Other Drivers” Sub-Forum.
By the way: I do not sign drivers upon request, which have not been modified by me.
Maybe you didn’t install your signed driver correctly? @Fernando - I think maybe he needs to know correct method to install such a driver?
Unless maybe it’s just not signed properly, if that’s the case maybe he needs help with that, but he’d need to upload file for you to check that I don’t know how you check such things.
I don’t want to ask anyone to sign a driver for me. I think i managed to sign it, but for some reason it appears as not signed upon installed. I just want to know if i have to do some additional steps after signing the .cat files.
You have to sign all driver files, which are listed within the related *.INF file (except the *.CAT file, but incl. the *.INF file itself).
The *.CAT file contains the digital signature and will be created by executing the command “Sign Driver 64.cmd” resp. “Sign Driver 32.cmd”.
I managed to sign all of the .dll and .sys files. But still facing the not digitally signed warning when selecting the driver from the device manager’s manual driver installation.
Which file types can be signed?
Edit: I signed all possible file types using the “*” key 
I even regenerated the .cat files. I’m missing something very basic but I can’t seem to figure it out…
@speter2 :
Questions:
1. Did you remove all *.CAT files from the related Driver folder, before you ran the “Sign driver” command?
2. Has the signature process been completed successfully?
3. What do you see, when you do a right-click onto your freshly created *.CAT file, choose the options “Properties” > “Digital Signatures”, click onto the name of the signer and then hit the button “Details”?
Not sure what went wrong, but I managed to get it working! I checked the .cat file again, and I noticed that the Digital Signature tab was gone, so I signed it again and it worked! Thank you so much!
Do you think I can post this driver in the forum, so other people can use it aswell?
@speter2 :
You’re welcome! It is fine, that you finally were able to solve your problem.
Not really.
Without the previous import of the related Digital Signature Certificate the usage of a modded driver doesn’t make much sense. Furthermore this Forum hasn’t been designed to give support for (modded) graphics drivers.
My advice: Add a statement, that interested Forum visitors may send you a PM.
I see. I’m not sure where should I share this driver… It’s been modified in order to provide support on Windows 8.1/8/7 for HD620 and UHD620 Intel gpus. As you may know, there aren’t any drivers for oldel OSes for Kaby Lake+ systems.
Any plans on making the forums modded drivers ready?
And thank you again for your help! (I even made a script for installing the certificate, I had a lot of fun! )