In Microsoft Forefront Threat Management Gateway (TMG) 2010, you can specify an exclusion list from HTTPS inspection, that is, the list of sites that are excluded from HTTPS inspection. You cannot define an inclusion list, that is, the list of sites for which the HTTPS inspection is applied.
To resolve this problem, install the service pack that is described in the following Microsoft Knowledge Base article:
2555840 Description of Service Pack 2 for Microsoft Forefront Threat Management Gateway 2010
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
There can only be one DomainNameSet in the inclusion list. If the inclusion list is set, the HTTPS Inspection Exclusion tab in the UI is disabled.
To set the inclusion list for HTTPS inspection, follow these steps:
Create a DomainNameSet for the HTTPS inspection inclusion list.
Copy the following script into Notepad save it with the file name ConfigureHTTPSiInclusionList.vbs.