> when I define the emf mime type with --assume
> emf=image/x-emf, HTTrack retrieve all my .emf
> images, they've the right size but the image cannot
> be displayed with any tool !!!

Any errors in hts-log.txt ? Can you look at the hts-cache/new.lst and tell me
what type is seen by httrack - by searching for the emf file in new.lst ?
Example:

10:59:28 621/621 U--M--	200 updated ('OK') text/html etag:""
<http://www.example.com/foo.emf>