Michael Beardmore wrote:
> I have developed a small application for clients to download files
> from the internet using tHttpCli. Generally it works OK without
> software firewalls blocking the communication however, every now and
> then, some software firewalls (eg Vet, Nortons, Mcafee, AVG,
> TrendMicro, Zone Alarm, etc.) will suddenly block the communication
> with no message or warning (generally after they have done an
> update). The client then needs to put in (or refresh) an exception
> into their software firewall/antivirus and everything is OK.
That is how most personal firewalls work. Unless there is no exception
configured they block. When your EXE has changed most personal firewalls
will block it as well. However they should always notify the user about
rejected connection attempts including some connection parameter like
IP and port number etc..
>
> The program first downloads files from a non password protected
> section of the server then downloads additional files from a password
> protected section of the server (not a https server). It is
> interesting to note that the firewalls only have a problem with the
> password protected section.
>
> I am guessing that when tHttpCli and the server are authenticating
> usernames & passwords it is not done on the usual Http port and hence
> the firewalls see this and block the communication.
Maybe, even though not very common.
If this is true, the firewall rule for you application should allow
connections to those ports as well, not just the default HTTP port 80.
> If this is true, is there some way to "force" tHttpCli to use the
> same port for username and password authentication, much like passive
> mode does for FTP?
No, a HTTP client connects to the server/port given in the URI.
A server may redirect a request to another URI, in this sense HTTP
already works like FTP passive mode.
--
Arno Garrels
--
To unsubscribe or change your settings for TWSocket mailing list
please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket
Visit our website at http://www.overbyte.be
