When working with web proxies, you may run across a variety of issues. This is because the web was not built to employ proxies. They are, in a sense, web exploits.
Proxies have a sliding spectrum of mistakes. Authentication via proxy server failed errors occur when software, servers, or websites anticipate one thing and get another. It's like receiving spiders in a "puppies" package. You get out of there quickly.
Less data means less mistakes. However, if the server passes enough data, it ceases to be a proxy and becomes a regular web operation.
But many individuals use proxies to connect anonymously, which poses issues. Proxying requests but stripping header data is sending one thing while expecting another.
This usually indicates the server believes you're someplace else and doesn't have much data about you to submit to analytics. The difference between anticipated and given data might create errors.
The authentication via proxy server failed error is that. A collection of software interacting with a proxy in a certain manner produces issues.
Forgiveness is heavenly, but not in this scenario. With this mistake for so long, you may even beg it. You may have been using proxies successfully for some time without running into this issue.
So What Is A Proxy Server?
Proxies are servers that act as intermediaries between a client and the Internet. It does this by intercepting communications between the sender and the recipient. Data is received at one port and sent to the rest of the network at another.