Most Common Web Server Error Messages.

Here is the list of most common web server error messages a web tester must know about:
1. 400 Bad File Request
Syntax used in the URL is incorrect e.g. uppercase letter should be lowercase letter, wrong punctuation marks.

2. 401 Unauthorized
Server encryption key from the client is missing or wrong password may have been entered.

3. 403 Forbidden/Access Denied
Special permission needed to access the site -- a password and/or username.

4. 404 File Not Found
Server cannot find the file you requested. File has either been moved or deleted, or you entered the wrong URL or document name.

5. 408 Request Timeout
Client stopped the request before the server finished retrieving it. A user will either hit the stop button, close the browser, or click on a link before the page loads. Usually occurs when servers are slow or file sizes are large.

6. 500 Internal Error
Couldn't retrieve the HTML document because of server-configuration problems. Contact site administrator.

7. 501 Not Implemented
Web server doesn't support a requested feature.

8. 502 Service Temporarily Overloaded
Server congestion; too many connections; high traffic. Keep trying until the page loads.

9. 503 Service Unavailable
Server busy, site may have moved ,or you lost your dial-up Internet connection.

10. Connection Refused by Host
Either you do not have permission to access the site or your password is incorrect.

11. File Contains No Data
Page is there but is not showing anything. Error occurs in the document. Attributed to bad table formatting, or stripped header information.

12. Bad File Request
Browser may not support the form or other coding you're trying to access.

13.Failed DNS Lookup
The Domain Name Server can't translate your domain request into a valid Internet address. Server may be busy or down, or incorrect URL was entered.
14. Host Unavailable
Host server down. Hit reload or go to the site later.
15. Unable to Locate Host
Host server is down, Internet connection is lost, or URL typed incorrectly.
Network Connection
16. Refused by the Server
The Web server is busy.