The server either does not recognize the request method, or it lacks the ability to fulfill the request. Why it occurs The error occurs when the Web server does not understand or support the HTTP method found in the HTTP data stream sent by the client. The method should be one of GET, OPTIONS, HEAD, POST, PUT, DELETE, TRACE, or CONNECT as defined by the HTTP protocol. If the method is valid but not supported by the Web server, upgrading the server might resolve the issue. Fixing the 501 error code Clients should specify a valid request type. If the Web server continues to respond incorrectly, consider upgrading the server. If you're registered with 100pulse, you'll receive alerts via email or SMS when a 501 status code error occurs.