> I have turned off robots.txt, set the bandwidth to 10KB/s,
> set the number of downloads to 1, set the browser identity
> to IE6... I don't get it. Why do these images show up fine
> in a browser, but not in HTTrack?
Ah, asp redirects to jpg..
First erase all default MIME types:
Set Options / Mime types : erase the default entry 
(something like asp,php.. <---> text/html)

Then ensure that you have in Scan rules defined:
+*.jpg

This should do the trick.