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In some cases the operating system may still not have imported the relevant Amazon Root CA1 certificate as trusted. In this case you need to manually import it in the computer certificates mmc (German: Computer Zertifikate verwalten) and there in the trusted root certificate authorities section. Yes, afterwards you will need to reboot the system. Here is the certifcate:
=> "Amazon Root CA 1,O" https://www.amazontrust.com/repository/
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