VS Code Proxy Settings for Extensions, CLI and Terminal Programs
The editor, extensions, CLI, and terminal programs can have different network paths. Separate a stored proxy login from the client making the failed request.
A remembered VS Code proxy login can coexist with a failed terminal or extension download. Identify the operation and process making the failed request before changing the stored account.
Core editor networking
VS Code's core proxy support comes from Chromium and normally follows system network settings. It supports common authenticated HTTP proxy schemes and can remember credentials in the OS credential store. That store is not automatically an account source for every program the editor launches.
If the remembered account is rejected, check the endpoint and advertised method. Certificate settings do not supply missing authentication.
Extensions and CLI requests
VS Code documents legacy settings such as http.proxy for extension and CLI scenarios. Check the editor version and the extension's own network interface: it may use another library, launch an executable, or run in another environment.
Integrated-terminal programs
npm, Git, pip, and other commands use their own supported proxy settings. Inspect the actual process environment. An existing terminal can retain old variables, and a remote terminal can run on another machine.
Marketplace access and extension artifact delivery can use different hosts. Preserve the hostname in the failed request; a successful catalog or login request does not establish artifact reachability.
Report the operation, process location, proxy endpoint, and first failed stage, with secrets removed. Those observations locate a 407, TLS error, or unreachable delivery host in the client that owns it.