The ProxySG does not determine the apparent data type of an object based on file extension. Instead, it looks at the attachment payload itself. The ProxySG sets the apparent data type to DOS/Windows Executable if it detects a Portable Executable header in the attachment. There is a large number of file types and extensions which use this format, so it is difficult to provide an exhaustive list of all file types and extensions.
However, the Portable Executable file format will be flagged as DOS/Windows Executable and will help determine whether or not a particular type of file is detected. The following is a list of common file types and extensions:
.cpl, .exe, .dll, .ocx, .sys, .scr, .drv, msstyles featured in Windows XP
For more information about Portable Executables, refer to the Wikipedia page at: