These numbered error codes are how the
server tells website visitors about an error encountered. There are
many different error codes that a server can deliver, but these are a
few of the more common codes.
401 : Unauthorized
Access to
the URL resource requires user authentication which either has not yet
been provided, or which has been provided but failed. This is commonly
known as password protection. Unless you have a good reason to do so,
it is not recommended to redirect a 401 error.
403 : Forbidden
The
request was a legal request, but the server is refusing to respond to
it. Unlike a 401 Unauthorized response, authenticating will make no
difference. This is usually due to a scripting or file permissions
issue.
404 : Not Found
This response code indicates that the
visitor was able to communicate with the server, but either the server
could not find what was requested, or it was configured not to fulfill
the request and not reveal the reason. Error 404 should not be confused
with "server not found" or similar errors, in which a connection to the
destination server cannot be made at all.
500 : Internal Server Error
Your
web server encountered an unexpected condition that prevented it from
fulfilling the request by the visitor. Basically, something has gone
wrong, but the server can not be more specific about the error
condition in its response to the visitor.
Got it! Thanks a lot again for hlipeng me out!