> I run into a website that uses some sort of anti-
> robotic software that analyze your browsing behavior 
> and ban your IP accordingly.

Have you looked at the error log?  That may say something about robots.txt
blocking certain files.  If this is the case, you could tell HTTrack to ignore
robots.txt (just use this respectfully.)

Alternatively, have you checked what "browser ID" HTTrack is using? You can
set this in the options.  Try something common like:

Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)