> I have just installed httrack 3.43-7 in windows 7. I
> downloading with only 4 simultaneous connections at
> 100 koBytes/s.
> 
> Why my setting doesn't work? 
Since 3.4x the security settings prevent more than 4 connections and 100KB/s
to avoid overloading sites.
You have to add (url box) the flag --disable-security-limits

If it's your site, fine, but don't abuse other:
<http://www.httrack.com/html/abuse.html#USERS>