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Trustpilot407 Proxy Authentication Required is the HTTP status code a proxy server returns when a request reaches it without valid credentials. The proxy has not contacted the website at all; it is asking the client to authenticate first.
The status is defined in section 15.5.8 of RFC 9110. It works like 401 Unauthorized, but for the proxy rather than the website. The response must include a Proxy-Authenticate header naming the scheme the proxy accepts, for example Proxy-Authenticate: Basic realm="proxy", and the client is expected to retry with a matching Proxy-Authorization header.
For https:// sites the 407 is the answer to the CONNECT request, before any TLS starts. Clients report it differently: curl shows the status in verbose mode, and Python requests raises a ProxyError that mentions 407.
A 407 means none of your requests reached the target, so it is never a block by the website and never an IP reputation problem. Fix the authentication and the requests go through. The usual causes:
USERNAME:PASSWORD@ part.@, :, #, / and % inside the username or password break parsing, so p@ss must be written p%40ss.Basic while the client offers another scheme, or in Python requests the credentials sit on the http key but not on the https key.Pass the credentials with -U (--proxy-user) so curl does not have to parse them out of the URL, and add -v to see the proxy's reply. Single quotes stop the shell from changing characters such as $ and \.
If an IP address prints, authentication works and the problem is in your application's proxy settings.
curl -v -x http://HOST:PORT -U 'USERNAME:PASSWORD' https://api.ipify.orgEncode the username and password with quote(..., safe=""), which escapes every reserved character, and put the same URL on both keys so https:// requests are authenticated too.
CleanProxies static ISP proxies accept username:password or up to 20 whitelisted IPv4 addresses, and the proxy errors guide covers the other status codes you may see.
from urllib.parse import quote
import requests
user = quote("USERNAME", safe="")
password = quote("PASSWORD", safe="")
proxy = f"http://{user}:{password}@HOST:PORT"
proxies = {"http": proxy, "https": proxy}
r = requests.get("https://api.ipify.org", proxies=proxies, timeout=30)
print(r.status_code, r.text)The CleanProxies proxy that fits best here, with a $4.99 trial to test it first.
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Terms that come up alongside 407 Proxy Authentication Required.
Straight answers about 407 Proxy Authentication Required.
A 401 comes from the website and asks for the site's own login. A 407 comes from the proxy and asks for the proxy credentials, before the request reaches the website.
