[Mailman-Users] mime type of psd file

Just tried: image/vnd.adobe.photoshop

as suggested. Still did not work. How do you look at the raw message to see what the Content_type: header for the attached part says it will be?

What is the mime type of a psd file?  I have tried  

: 

application/octet-stream 

image/psd 

image/x-psd 
and they don't work. 
Robert