Hi mail139, I'm not familiar with that VPN.

Does it run at the system level, or is it an add-on, or a combination (add-on coordinating with external software)?

You could check your Firefox connection setting here:

• Mac: "3-bar" menu button (or Firefox menu) > Preferences
• Windows: "3-bar" menu button (or Tools menu) > Options
• Linux: "3-bar" menu button (or Edit menu) > Preferences
• Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

In the search box at the top of the page, type proxy and Firefox should filter to the "Settings" button, which you can click.

The default of "Use system proxy settings" piggybacks on your system setting. "Auto-detect" can lead to a flaky connection. You may want to try "No proxy".

Any difference in working with your VPN?

You can also check the DNS Lookup tool on the about:networking page.