This policy setting determines whether Internet Explorer MIME sniffing will prevent promotion of a file of one type to a ...

This policy setting determines whether Internet Explorer MIME sniffing will prevent promotion of a file of one type to a more dangerous file type.

If you enable this policy setting, MIME sniffing will never promote a file of one type to a more dangerous file type.

If you disable this policy setting, Internet Explorer processes will allow a MIME sniff promoting a file of one type to a more dangerous file type.

If you do not configure this policy setting, MIME sniffing will never promote a file of one type to a more dangerous file type.