MIME Property
Specifies one or more MIME (Multipurpose Internet Mail Extension) types to be associated with the selected file type on the target computer. MIME types are used to specify how client Web browsers and mail applications will handle binary data.
Once you have set the MIME property, your installed product will treat e-mail and Internet files of that MIME type the same as files specified in the Extensions property.
Remarks
The MIME property takes the form application/type where application represents either your application or a class of applications (such as video), and type represents a unique MIME type. The forward slash is required. You can specify more than one MIME property by separating the properties with a semicolon.