While registering Digital Signature Certificate (DSC) on DVAT Site and error shows “Windows has found a problem with this file. ncodePKIDSC.cab. Unknown Publisher.”
User are advised to change the security settings of Internet option and should “allow software to run or install even if the signature is invalid” as shown in the given picture:
Control Panel >> Folder Option >> View >> Show hidden files, folders and drives
Restart the computer.
For more information, refer to the link.