When Does .NET 9 Pick Up Windows Proxy Changes?
HttpWindowsProxy refreshes current-user system settings; explicit objects, environment defaults and active streams have different lifetimes.
Identify the source first:
| Source | Effect of .NET 9 Windows registry watcher |
|---|---|
| Application handler.Proxy object | Does not rewrite that explicit object |
| Environment-selected default | Does not turn environment into a live update service |
| Windows system proxy path | HttpWindowsProxy watches current-user Internet Settings and refreshes after notification |
Current user can be a service account rather than the desktop user whose Settings changed.
Do not rebuild policy from only WinHttpGetIEProxyConfigForCurrentUser's manual Proxy field: it also returns bypass and automatic inputs. One fixed WebProxy discards destination-dependent PAC decisions.
Check subsequent connection selection, not movement of an existing stream. Older runtimes or application-owned policy need their supported update lifecycle; repeatedly restarting Windows does not explain which source was stale.