Open Internet Services Manager from the Administrative Tools. Right click on the OWA website where you previously created a CSR and choose "Properties". Press the "Directory Security" tab and then click "Server Certificate" in the "Secure Communications" section.

When the wizard starts, choose "Process the pending request..." and press "Next". In the next screen, click "Browse" and then click the drop down box to choose "All Files *.*". Now, navigate to the folder where you stored the .p7b file and select it. Press "OK" and then click next. Verify that the port number is correct (customers who are renewing a certificate will not see this step). The default SSL port is 443. Finish the wizard and your certificate and intermediates will be installed.

Download the GlobalSign Root certificate

Download the GlobalSign Partners certificate

Download the TrustwaveCA certificate

Move all three files onto the Windows Server and complete the following three steps:

Double-click the GSRoot.crt certificate, press "Install Certificate", press "Next", and then choose "Place all certificates in the following store". Click "Browse", and then "Show Physical Stores". Click the plus (+) sign next to "Trusted Root Certification Authorities" and click "Local Computer" underneath it. Click "OK", then "Next" and then "Finish".

Double-click the GSInt.crt certificate, press "Install Certificate", press "Next", and then choose "Place all certificates in the following store". Click "Browse", and then "Show Physical Stores". Click the plus (+) sign next to "Intermediate Certification Authorities" and click "Local Computer" underneath it. Click "OK", then "Next" and then "Finish".

Double-click the TrustwaveCA.crt certificate, press "Install Certificate", press "Next", and then choose "Place all certificates in the following store". Click "Browse", and then "Show Physical Stores". Click the plus (+) sign next to "Intermediate Certification Authorities" and click "Local Computer" underneath it. Click "OK", then "Next" and then "Finish".