Applet web communication

I have a Visual Basic program that collects data from a number of PLC's using OPC. The program also opens a WinSock Listener on port 80.
What I want to do is to open a web browser and enter the address of the url where the visual basic program is running. The visual basic program will send an applet to the web page which will start and connect back to the visual basic program which would then continuously update the applet page with the PLC data.
So far the applet loads but will not init. It may be that I am trying to connect back to the visual basic program on port 5719 which I was using on the local network with vb client programs. Should I just try to connect back on port 80?
I read somewhere that it needs to be digitally signed in order to run.
Can anyone tell me what I need to do?
Thank you in advance.

An applet can connect to the server it came from (not sure if it can connect to another port).
You could try to sign it:
http://forum.java.sun.com/thread.jsp?forum=63&thread=524815
second post
And you could try to check the full trace.
To turn the full trace on (windows) you can start the java console, to be found here:
C:\Program Files\Java\j2re1.4...\bin\jpicpl32.exe
In the advanced tab you can fill in something for runtime parameters fill in this:
-Djavaplugin.trace=true -Djavaplugin.trace.option=basic|net|security|ext|liveconnect
if you cannot start the java console check here:
C:\Documents and Settings\userName\Application Data\Sun\Java\Deployment\deployment.properties
I think for linux this is somewhere in youruserdir/java (hidden directory)
add or change the following line:
javaplugin.jre.params=-Djavaplugin.trace\=true -Djavaplugin.trace.option\=basic|net|security|ext|liveconnect
for 1.5:
deployment.javapi.jre.1.5.0.args=-Djavaplugin.trace\=true -Djavaplugin.trace.option\=basic|net|security|ext|liveconnect
The trace is here:
C:\Documents and Settings\your user\Application Data\Sun\Java\Deployment\log\plugin...log
I think for linux this is somewhere in youruserdir/java (hidden directory)

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