Likely the page is was incorrectly built. In this situation, the request contains a text that is too long.
A request is an item in the web page that tells the server special information. For example, it might specify the language to use or authentication information. There are more than twenty different types of requests.
Example
Server Error
404.15 - Query-String too long.
This URL is denied because its Query-String is longer than specified by configuration.
Error messages will differ depending on the web server and if replaced by the web site designers.
Occurrences
Frequency is relative to other Internet warnings and errors.
Solutions and Fixes
This issue can only be fixed by the web site owner.
Notify Webmaster
7
You might notify the webmaster about the issue. Include the error number and the address (URL) where the error occurred along with any other relevant details.
Many sites use an email address in the form webmaster@sitename.com where you replace sitename.com with the web sites address (don't include a www). Keep in mind with the amount of spam, they may use a different address and/or it might get ignored. Check the websites' contact information to get reliable contact information.
FaultWire Staff Posted: 8-Oct-2008
Official Explanation
The request contains a query string that is longer than the limit that is allowed for the server.
"404.15 - Query string too long" is only supported by Microsoft IIS (Internet Information Services) web server version 7 and later.
The four hundred series of errors indicate something was sent to the remote web server incorrectly.
While we believe this information up to date and accurate, FAQware is not responsible for any inaccuracies. If you find something that is out of date or inaccurate, please let us know at
so we can correct it.
The request contains a query string that is longer than the limit that is allowed for the server. 
