When you rely on proxies to run your scripts, manage multiple accounts, or localize content, connection errors can be frustrating and disruptive. In this guide, we’ll walk through the most common proxy-related errors and exactly how to fix them, step by step.
What it means: Your proxy requires authentication, but your client hasn’t provided valid credentials.
How to fix it:
- ProxiesThatWork uses IP authentication only, so make sure your current IP address is correctly whitelisted in your dashboard.
- If you're still seeing this error, clear your script or browser of any cached proxy settings that might be attempting username/password auth.
What it means: The server you're connecting to is blocking access, possibly due to proxy use.
How to fix it:
- Switch to a different proxy IP.
- Add realistic headers like User-Agent, Accept, and Referer.
- Use proper delay and throttling to mimic human-like behavior.
- Use IPs with less history of aggressive scraping or bot-like activity.
What it means: Your request is taking too long and the server or proxy is timing out.
How to fix it:
- Make sure the proxy is active and your IP is whitelisted.
- Test the proxy manually using a browser or Curl.
- Increase your timeout settings in code. For Python Requests:
requests.get(url, proxies=proxy_dict, timeout=30)
- Switch to another proxy IP if one is temporarily unresponsive.
What it means: The proxy server received an invalid response from the upstream server.
How to fix it:
- Confirm the target website is online.
- Rotate to a different proxy IP.
- Use a different target endpoint if possible.
What it means: The target server is rejecting the connection.
How to fix it:
- Confirm your proxy IP and port are correct.
- Double-check that your IP is whitelisted.
- Use tools like telnet or curl to manually test the connection.
- Try another proxy IP if needed.
What it means: The secure connection between your proxy and the target server is failing.
How to fix it:
- Make sure the proxy supports HTTPS (ProxiesThatWork HTTP proxies are compatible).
- In development environments, you may use verify=False (not recommended for production):
requests.get(url, proxies=proxy_dict, verify=False)
- Ensure your system has up-to-date root certificates.
What it means: Your proxy or local machine cannot resolve the domain name.
How to fix it:
- Confirm the target site is live and accessible outside of the proxy.
- Use public DNS like 8.8.8.8 or 1.1.1.1.
- Configure DNS resolution properly on your system or in your script.
Testing helps isolate whether the issue is with the proxy itself or your script/tool.
Command line test:
curl -x http://proxy_address:port https://api.ipify.org
In Python:
import requests
proxies = {
"http": "http://proxy_address:port",
"https": "http://proxy_address:port",
}
response = requests.get("https://api.ipify.org", proxies=proxies, timeout=10)
print(response.text)
If the IP returned isn’t yours, the proxy is working.
- Use multiple IPs and rotate them manually if needed.
- Add timeouts and retries in your code.
- Respect robots.txt for ethical scraping.
- Monitor success rate and replace underperforming proxies.
- Avoid overloading a single IP with rapid requests.
- Is your IP whitelisted on the proxy provider dashboard?
- Are you using the correct port and proxy protocol (HTTP only)?
- Does the target site block datacenter proxies?
- Are your headers and user-agent realistic?
Proxy errors can feel like a black box, especially when you're under pressure to deliver data or meet a deadline. But with a structured approach, you can resolve most issues quickly.
Bookmark this guide, and the next time you hit a roadblock, come back and work through the checklist. Because when your proxies work, your workflows do too.
