This check determines whether the Office Web Apps infrastructure is configured to use SSL connections.
Office Web Apps Server delivers browser-based versions of Office apps in an on-premises environment, giving users more flexibility and collaboration opportunities. Starting with Office Web Apps Server 2013, it is decoupled from the SharePoint Server so it can be used independently from it and be used with other products like Lync 2013, Exchange 2013 and even non-Microsoft solutions. This provides a consistent user experience, regardless of the product used. In addition, Microsoft can add new features to Office Web Apps independently from SharePoint.
For Office Web Apps to be used with the SharePoint, Web Application Open Platform Interface (WOPI) endpoints must be configured on the Office Web Apps server(s) and a WOPI binding must be created between SharePoint and the Office Web Apps infrastructure. In test environments, you may use unsecured HTTP interfaces; however, using SSL-secured HTTPS interfaces is strongly recommended for production environments.
Verify that the Office Web Apps WOPI endpoints are SSL secured. Office Web Apps Server uses zones to determine which URL (internal or external) and which protocol (HTTP or HTTPS) to use when it communicates with the host, which in this case is SharePoint 2013. By default, SharePoint Server 2013 uses the internal-HTTPS zone. Verify that this is the current zone by running the following command:
Depending on your environment, you might have to change the WOPI zone. If you have a SharePoint farm that’s both internal and external, specify external. If you have a SharePoint farm that’s internal only, specify internal. If the setting is internal-HTTPS and the SharePoint farm is internal only, you can skip the following step. If you have a SharePoint farm that’s internal and external, you need to run the following command to change the zone to external-HTTPS:
Set-SPWOPIZone -zone "external-https"
For more information and detailed setup instructions, please read articles from the Additional information section.
Additional information can be found in the following articles: