Follow these steps if you selected the Upload X509 Certificate (DER) radio button on the User Authentication Details page. These steps place the certificate in the server keystore for the Registry and load the certificate into the web browser.
The third-party certificate must be in X.509 format. Typically, the certificate is in a file with the suffix .cer.
On the User Authentication Details page, click the Choose Certificate File button.
In the File Upload dialog box, click the Browse button to locate the file to upload, then click Upload File.
The name of the file appears on the User Authentication Details page next to the Choose Certificate File button.
On the Step 4: Load Key to Web browser page, follow the instructions to import the certificate into your web browser if it is not already there.