| 400 Bad File Request | Usually means the syntax used in the URL is incorrect. Example : uppercase letter should be lower case letter or wrong puctuation marks. |
| 401 Unauthorized | The server is looking for some encryption key from the client and is not getting it or a wrong password may have been entered. Try again and pay close attention to CaSe LeTtErInG. |
| 403 Forbidden/Access Denied | Similar to 401. Special permission is required to access the site (usually a password or username). Another instance may be caused by not having the proper permissions set up on the server. |
| 404 File Not Found | The server cannot find the file (web page) you requested. |
| 408 Request Timeout | Client stopped the request before the server finished retrieving it. A visitor will either hit the STOP button or close the browser or click on a lin before the page loads. |
| 500 Internal Error | Could not retrieve the document because of server-configuration problems. |
| 501 Not Implemented | Web server does not support a requested feature. |
| 502 Service Temporarily Overloaded | Server congestion. Too many connections at one time. High traffic. |
| 503 Service Unavailable | Server busy, site may have moved or you lost your dialup connection. |
