It sounds as if you have already undertaken a fair amount of troubleshooting. I have one more step you can try and if this does not resolve the issue, i would recommend a fresh Windows Installation.
Navigate to the following location.
Inside the A464 folder run the A4 installer package.
Navigate back to the Core-Static folder and run the CCC Slim installer package.
Restart your system and determine if the issue is resolved.
It you are still unable to open additional settings, please perform the following actions.
1 of 1 people found this helpful
I have fixed the issue by downloading a d3d9.dll from a website and dropping it into the CNext folder! Thank you for your help regardless.
Could I get the link to where you found that file? I'm having the same exact issue and have tried everything but reformatting. Thanks