Display Window does not load if proxy server set

Our organization is looking at offering processing workshops on our Learning Centre computers.

However on the Windows 10 PCs with a proxy server set processing v3.4 will not load the Display Window. As soon as the proxy is disabled the Display Window pops open.

Example code
ellipse(50, 50, 80, 80);

Turn proxy off/on
Control Panel > Internet Options > Connections > LAN settings > Proxy server
Tick “Use a proxy server …” and enter proxy server details and port.
“Use automatic configuration script” also prevents the Display Window from loading.

In Task Manager javaw.exe is running and java.exe appears too when the program is run (and the Display Windows does NOT load).

I added processing.org to the proxy server exceptions list (on the computer and then on the proxy server bypass list) but this has not solved the problem.

I installed Wireshark to ascertain what type of Internet connection is being used when the Display Window opens. I didn’t see any evidence of Internet traffic while this script ran successfully with the proxy not set.

Processing v2 does load the Display Windows on the same Windows 10 PC with a proxy set.

Turning the proxy off for the workshop is not an option either.

Has anyone successfully run processing 3.4 (Windows) on a computer with the proxy set?

Thank you.

Check these links:




Thank you for this link

Editing the user’s preference file (C:\Users[user]\AppData\Roaming\Processing.txt) fixed the problem. Specifically adding our proxy details to lines



Editing the processing-3.4copy\processing-3.4\java\lib\net.properties did not work for me.