What a 501 Not Implemented Error is, and How to Fix itThough uncommon, seeing an HTTP 501 Not Implemented error status code can be an alarming experience for those who see it—especially when it’s on your website. However, the difference is that a 405 Not Allowed error is a server administrator issue, while a 501 Not Implemented error is a hosting server issue. How to fix the HTTP 501 Not Implemented ErrorThere are four ways to address a 501 error on a website:Reload the page. How to Fix the HTTP 501 Not Implemented Error If You Manage the ServerFixing this issue when you’re the server host is a whole different process. Here are some ways you can fix an HTTP 501 Not Implemented Error if you manage your server:Check if your server supports the requested feature.