Why is my proxy returning connection errors?

Most connection errors trace back to one of a handful of causes. Work through this list before assuming something is broken on our end.

Checklist

1. 1Check your balance on Add balance — a depleted balance stops requests from routing.
2. 2Confirm the host and port exactly match a batch from Generate proxies — ports are tied to a specific session, not interchangeable.
3. 3Re-copy your username and password — a stray space from copy-pasting is a common silent failure.
4. 4Try a plain cURL request (see Using proxies with cURL) to isolate whether the issue is the proxy or your application code.
5. 5Check Usage for unusually high recent consumption — if a script is looping and burning bandwidth faster than expected, requests can start failing once balance runs out mid-session.

If it's intermittent, not constant

Occasional failures on rotating sessions are normal at scale — a small percentage of any large IP pool will be temporarily unavailable at any given moment. Build retry logic into your client rather than treating a single failed request as a systemic problem. If failure rates climb well above what feels normal for your target site, see Target site blocks next.