> You need to tell the second instant what port to
> listen to. <http://www.httrack.com/history.txt> states
> that 3.40-2 contains a new --port option for
> webhttrack

I don't think so, since it manages to figure out a new, unused port all by
itself.

However, it seems like it gets confused when the second browser exits
immediately. When the browser is running and you start another instance then
the new instance tells the already running instance to open a new window and
then the new instance exits. Pretty much all browsers work this way.

Some browsers support multiple profiles, e.g., you can run "firefox -a 1 -P
foo ; firefox -a 2 -P bar" to run two instances of firefox, with the profiles
foo and bar, respectively. Webhttrack doesn't seem to use any such features,
though.