I'm using PRTG with just the Full Web Page sensors.
I am testing our upstream proxy server, which doesn't require authorisation. At the device level I have configured the proxy server and port. I have added www.google.co.uk to test, and it says the resource cannot be found. I have tried the Chromium, Internet Explorer, and PhantomJS engines but still cannot get the page to work.
Both Chrome and IE on the PC are working without issue using these same proxy details.
I'm using PRTG without issue through our internal proxy server, although that requires NTLM authentication. Our internal proxy server then connects to the upstream proxy server I'm trying to test.
Can anyone help?