In Windows Server 2008, and possibly other Windows versions, we have seen instances that renewing a certificate and the installing it on the server does not propagate correctly.

Digicert has a certificate utility that can be used to generate the required CSR for all certificate companies and is able to assist in installing the certificates onto your server.

To get the Digicert Certificate Utility for Windows, you can download it from: https://www.digicert.com/util/

Instructions on installing a new certificate:

1. Use the Digicert application to delete the original cert from the system.
2. Request a new SSL registration cert request from within digicert.
3. Submit that request back to the certificate authority you are currently using.
4. Once the new cert has been issued, download the new cert and then use the Digicert app to install back onto machine.

To test the certificate, open up a command prompt and telnet to the server via port 25. Issue an EHLO command, and in the list of available commands, you will see a 250-STARTTLS command. This means that the certificate is accepted, and the server is ready to connect via SSL/TLS

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