Proxy works for Plugins but not updater

[Simon Garratt]

In investigating, I have set and then cleared the proxy (back to empty and 0).

With it cleared, when I click ? > Update Notepad++, I get ‘Could not resolve host: notepad-plus-plus.org’.
When I go to Plugins > Plugins Admin, I see a list of plugins. I select, say, CsvQuery, which is not installed, click Install, and see the ‘Notepad++ is about to exit’ prompt. I click Yes, see the UAC prompt, click Yes, then see what I think is a downloading progress bar which appears to stick at 0% but disappears very quickly, Notepad++ restarts and the plugin hasn’t been installed.

I quit, restart as admin, and use ? > Set Updates Proxy… to the FQDN of my proxy server and port 80.

I quit, restart (not as admin) and click ? > Update Notepad++. I get a dialog which says 'Received HTTP code 407 from proxy after CONNECT. [I believe our proxy uses Integrated Windows Authentication with the browser.]
I go to Plugins > Plugins Admin, select CsvQuery and click Install, and see the ‘Notepad++ is about to exit’ prompt. I click Yes, see the UAC prompt, then click Yes, see the progress bar go to the top (twice?). Notepad++ restarts and CsvQuery has been installed.

There appears to be a difference between how Plugins Admin and the Notepad++ updater handle proxy servers.

I’m running 32-bit v7.8.9 which I had to install manually because the updater wouldn’t work (but I hadn’t tried setting a proxy before this),