Encountering erroneous proxy messages is a common issue in online data management and web scraping, with error codes serving as vital indicators for diagnosing and resolving data delivery problems. The article provides an overview of various HTTP proxy error codes, categorizing them into client-side and server-side errors, and explaining their meanings and typical conditions under which they arise. It covers 3xx codes like 301 and 302 for redirects, 4xx codes such as 400 for bad requests and 403 for forbidden access, and 5xx codes like 500 for server errors. Each error code is accompanied by practical advice on troubleshooting and solutions, such as handling redirects, verifying request syntax, and implementing retry strategies to reduce the incidence of errors. Additionally, the article emphasizes the importance of understanding proxy settings and consulting documentation to effectively manage HTTP errors during web scraping.