Please upload your file to the correct directory. To make sure the authorization is successful make sure the file is viewable at both yourdomain.com/file and subdomain.yourdomain.com/file.

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What if I can only use one certificate file? Can I switch my method of Domain Control validation from Email to File, or vice versa? I entered in the wrong common name, how do I change it? The CSR cannot be decoded. What does that mean and what should I do?