# Errors and status codes

Source: https://ipvolt.com/docs/errors
Markdown: https://ipvolt.com/docs/errors.md

[Home](https://ipvolt.com/index.md) / [Docs](https://ipvolt.com/docs.md) / [Errors and status codes](https://ipvolt.com/docs/errors.md)

Section: Build
Updated: 2026-11-05
Author: ipvolt

What 407, 403, 502, 503, WRONG_VERSION_NUMBER and other proxy errors mean with an ipvolt mobile proxy, and the guide that fixes each one.

Most proxy errors say which side failed: your client, the proxy, or the website behind it. Find the message you see, then follow the guide for the exact fix.

## Messages and what they mean

| What you see | Usually means | Guide |
| --- | --- | --- |
| `407 Proxy Authentication Required` | The username or password did not reach the proxy, or is wrong. | [Fix proxy error 407](/guides/fix-proxy-error-407) |
| `CONNECT tunnel failed, response 403` | The proxy or a firewall on your side refused that destination. | [CONNECT tunnel failed, response 403](/blog/connect-tunnel-failed-403) |
| `502`, `503` or `504` while the tunnel opens | The proxy could not reach the website, or the device was offline or rotating. | [Tunnel connection failed: 502](/guides/fix-proxy-tunnel-502-503) |
| A `502` response after the tunnel opened | The website, or something in front of it, returned the error. | [Tunnel connection failed: 502](/guides/fix-proxy-tunnel-502-503) |
| `Proxy CONNECT aborted` or a closed connection with no status | Often the wrong port or protocol, or a rotation in progress. | [Endpoints and protocols](/docs/endpoints) |
| `SSL: WRONG_VERSION_NUMBER` | An `https://` proxy URL on the HTTP port. | [SSL WRONG_VERSION_NUMBER behind a proxy](/guides/fix-ssl-wrong-version-number-proxy) |
| `net::ERR_TUNNEL_CONNECTION_FAILED` | Chromium could not open the tunnel. | [Fix ERR_TUNNEL_CONNECTION_FAILED](/guides/fix-err-tunnel-connection-failed) |
| `TypeError: fetch failed` in Node.js | The real cause is in `err.cause`. | [Fix Node.js fetch failed behind a proxy](/guides/fix-node-fetch-failed-proxy) |
| `Missing dependencies for SOCKS support` | A `socks5h://` URL without the SOCKS extra installed. | [Fix Missing dependencies for SOCKS support](/guides/fix-missing-dependencies-for-socks-support) |
| Timeouts | One of DNS, connect, tunnel or response took too long. | [Troubleshoot proxy timeouts](/guides/proxy-timeout-troubleshooting) |

## Check one request first

Before changing your application, run one request with curl and print both status codes:

```sh
curl -sS -o /dev/null -x "http://USERNAME:PASSWORD@HOST:HTTP_PORT" \
  -w 'connect=%{http_connect} http=%{http_code} exit=%{exitcode}\n' \
  https://api.ipify.org
```

`connect` is the proxy's answer to the tunnel request and `http` is the website's answer. If curl works and your application does not, compare how the application passes the proxy settings.

## Check the device

The dashboard shows whether the device is online, its outgoing IP and when the rental ends. An expired rental stops working; see [Billing and renewals](/docs/billing). If a website blocks the current IP, rotating gives the device a new one, although the carrier can return the same IP.

## Contact support

If the device still does not work, email hello@ipvolt.com with the device name, its outgoing IP, the order number from your dashboard, what you tried (rotating, HTTP and SOCKS5) and the exact error. Never include your password. [Support](/support) lists reply times.

## More documentation

- Previous: [Integrations](https://ipvolt.com/docs/integrations.md)
- Next: [Billing and renewals](https://ipvolt.com/docs/billing.md)
- [All documentation](https://ipvolt.com/docs.md)