Troubleshooting

Errors

Every HTTP status and SOCKS5 reply code the gateway returns, what each one means, and what to do about it.

Updated Sep 15, 2026 · 2 min read

The gateway reports problems as a normal HTTP status (for HTTP/HTTPS CONNECT) or a SOCKS5 reply code (for SOCKS5). Both protocols cover the same set of situations:

HTTP	SOCKS5 reply	Meaning
`407`	`0x01` (auth failed)	Unknown login, wrong password, paused credential or invalid username option.
`402`	`0x02`	Allowance exhausted — no quota and no USD balance.
`429`	`0x02`	Too many concurrent connections for your account.
`502`	`0x01`	Upstream network rejected the connection (e.g. unsupported target).
`503`	`0x02` (maintenance) / auth status `0x01` (backend unavailable)	Gateway in maintenance or temporarily unavailable.
`504`	`0x04`	Upstream timeout while connecting to the target.

407 — Proxy Authentication Required

Something about the credential is wrong: the login doesn't exist, the password doesn't match, the credential is paused, or a -key-value targeting option is malformed or out of order.

What to do: check the login and password under Proxies (rotate the password if you're not sure it's current), and verify the username suffix against Targeting — lowercase values, correct key order, no unrecognized keys.

curl -x "http://ofp_0123abcd:PASSWORD@proxy.oneforproxy.com:8080" https://api.ipify.org

402 — Payment Required

Your traffic package quota is used up and your USD balance can't cover pay-as-you-go billing either.

What to do: top up your balance or buy a traffic package on Billing — see Billing and packages and Pricing.

429 — Too Many Requests

You've hit the concurrent-connection limit for your account.

What to do: close idle connections, add connection pooling/reuse in your client, or lower how many requests you run in parallel.

502 — Bad Gateway

The upstream network refused the connection — often an unsupported or blocked target site, not a problem with your credential.

What to do: retry the request; if it keeps failing for the same target, try different targeting (a different -country- or -asn-) or confirm the target itself is reachable from a normal connection.

503 — Service Unavailable

The gateway is in maintenance or temporarily unavailable.

What to do: back off and retry after a short delay. This isn't something a credential or username change fixes.

504 — Gateway Timeout

The gateway couldn't connect to the target in time.

What to do: retry, and if it's persistent for one target, try a different -country-/-asn- or a longer client-side timeout.

General advice

Treat 429, 503 and 504 as retryable with backoff, and 407/402 as configuration problems to fix before retrying — hammering the gateway with the same bad credential or exhausted balance just produces more 407s or 402s. Client-side examples that catch these are in curl, Python and Node.js. The canonical version of this table lives in the Docs.