How to Allow Unknown MIME Types in IIS 7

1. Click 'Start' and type 'Internet Information Services.' Click 'Internet Information Services (IIS) Manager' from the result list.

2. Click 'Features' to change to the feature view, then double-click 'MIME Types.'

3. Click 'Add' in the 'Actions' section of the screen, located on the right-side panel.

4. Type '*!' as the file extension type. This wildcard represents all unknown files.

5. Type 'application/octet-stream' in the text box labeled 'MIME type.' This is a generic MIME type that will tell the browser to treat it as a binary file. In all major browsers, this corresponds to asking the user to save the file to their hard drive.