A proxy error means something went wrong between your device and the proxy server handling your connection. The request didn't go through — because the proxy was misconfigured, the server was unreachable, or access was blocked somewhere along the way.
If you've ever wondered what is a proxy error and why it keeps showing up, you're in the right place. This guide explains the most common proxy errors, what causes them, and how to fix each one. Whether you're dealing with a one-off browser error or troubleshooting a broken network setup, you'll find a clear answer here.
What is a proxy error?
A proxy error is an HTTP error status. It shows up when you try to reach a website through a proxy server, but the server can't complete the request – because of a network issue, a misconfiguration, an outage, or an unsupported feature. The specific error code tells you where things went wrong and points you toward the right fix.
HTTP responses are grouped into five status classes, each identified by the first digit of the code.
| Status code class | Proxy error meaning |
|---|---|
| 1xx informational response | The server has received the request. It’s now processing it. |
| 2xx successful | The server has received and accepted the request. |
| 3xx redirection | Extra actions are needed to complete the request. |
| 4xx client error | The request contains errors and cannot be completed. |
| 5xx server error | The server failed to carry out a seemingly valid request. |
The 1xx and 2xx codes are informational – no action needed. The 3xx, 4xx, and 5xx codes signal an actual problem that requires your attention.
Proxy error meaning: each one explained
This guide covers the generic proxy status codes that most proxy servers and websites use. Keep in mind that some providers repurpose the same codes for different reasons, so there may be edge cases where the cause differs from what's described here.
Here's what each code means, starting from the top.
100 – Continue
The 1xx codes appear while a server is still processing a request — they're relatively rare in practice. The 100 code means the server has received your request header and you can go ahead and send the body of the request.
101 – Switching Protocols
A 101 code means your browser asked the server to switch communication protocols mid-transmission – and the server agreed. The response is the server's acknowledgment that it's making the switch.
102 – Processing (WebDAV)
When a client sends a complex request with multiple requirements, the server may need extra time to work through it. The 102 code lets the client know the request was received and is being processed — preventing a timeout on your end.
103 – Early Hints
The 103 code means the server is about to send a final response. It uses this informational response to share header fields in advance, giving the client a head start before the full response arrives.
301 – Moved Permanently
A 301 code means a permanent redirect is in place for the original URL — the server is forwarding you to a different address. This is rarely a real problem, since most browsers and scrapers follow the new URL automatically.
305 – Use Proxy
The 305 code appears when a requested web server can only be accessed through a proxy. It's a deprecated code, meaning it's no longer recommended due to security concerns, so you're unlikely to run into it.
The fix: Connect to a proxy server and retry the request.
306 – Switch Proxy
Unlike the 305, the 306 code assumes you're already using a proxy — it's telling you to switch to a different one. This code is also deprecated and rarely seen today.
The fix: Connect using a different proxy server.
307 – Temporary Redirect
A 307 code means you're being temporarily redirected to a different location to access the resource you requested.
The fix: Follow the redirect and send the request again.
400 – Bad Request
The 400 error is a common one. It means the server can't process your request — usually because of invalid formatting, malformed syntax, or a routing issue.
The fix: Review your request to make sure all required information is present and formatted correctly, then try again.
401 – Unauthorized
A 401 code means the resource you're trying to access requires authentication. You'll need to provide valid credentials to get through. Keep in mind that scraping data behind authentication walls may be illegal or unethical, depending on the context.
The fix: Provide the required authorization details. For example, ensure that the correct authentication credentials (username and password) are used for the request.
403 – Forbidden
The 403 error is intentionally vague — it just means access is forbidden, without specifying why. It could mean you're trying to perform an action reserved for site administrators, or that you're logged in with the wrong credentials.
404 – Not Found
A 404 means the resource you're looking for isn't there. The URL may be wrong, the page may have moved without a redirect, or it simply no longer exists.
The fix: For starters, you can double-check the URL and try again. You can also clear your browser cache and cookies, then try reloading the page.
407 – Proxy Authentication Required
The 407 code is a specific type of proxy error — it means your tool isn't authenticated correctly with the proxy server. This can happen if you've entered the wrong credentials or haven't whitelisted your IP in the proxy settings.
The fix: Update your proxy settings with the correct credentials and whitelisted IPs, and make sure all required information is included in the request. If the problem persists, contact your proxy provider.
408 – Request Timeout
A 408 code means your client didn't complete the request within the time the server was willing to wait. A slow or dropped internet connection is the most common cause.
The fix: Check your connection and retry. If the error keeps coming up, check your web server's load.
429 – Too Many Requests
The 429 error means you've sent too many requests from the same IP in a short period of time. The server flags this as bot-like behavior and cuts off access. Some proxy providers also use this code to enforce their own rate limits before requests even reach the target server.
The fix: Rotate your IP address and add delays between requests. You can also use Residential Proxies that rotate automatically, so you don't have to manage this manually.
502 – Bad Gateway
A 502 error means the server acting as a gateway or proxy received an invalid response from an upstream server.
The fix: Clear your cache and cookies and try again. If that doesn't work, try changing your DNS or making the request without a proxy.
503 – Service Unavailable
The 503 code means the server is temporarily unavailable — either because it's overloaded or undergoing planned maintenance. It can also mean your proxy IP has been identified and blocked by the target website, in which case switching to a different proxy should do the trick.
The fix: First of all, you should verify the legal restrictions in your jurisdiction to understand why the content is blocked. Then, you can use a VPN or proxies to rotate your IP address.
Choosing the right provider
Sometimes, a proxy error meaning might be less about your setup and more about the proxies themselves. Low-quality IPs get blocked faster, shared pools get rate-limited more often, and unreliable infrastructure leads to more timeouts and gateway errors. Choosing a solid proxy provider reduces how often you run into these codes in the first place.
Oxylabs proxy servers are one of the strongest options on the market — with a vast residential proxy and datacenter proxy network, automatic IP rotation, and reliable uptime, many of the errors covered in this guide become much less frequent. If you're looking for alternatives, Decodo, Webshare, or ScrapingBee are all worth considering depending on your use case and budget.
Wrapping up
Understanding proxy error meanings comes down to knowing a handful of root causes – blocked IPs, wrong credentials, or server issues. Once you know what the code means, the fix is usually straightforward.
