404.20 for long url in MVC 3

I get 404.20 error as result on request (long url). If I decrease length of url all became ok.

For example

https://almauktg98m6wotn34q0e.****.***/SurfT/gp/html/script/_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

result in 404.20 but for

https://almauktg98m6wotn34q0e.****.***/SurfT/gp/html/script/_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

all ok.

What can cause this problem?

I'm using IIS 8 + vs 2012 + windows 8

Maximum 256 character limit between slashes

To send such data is better to use POST.

Also you can increase maximum url length, defined in Web.config (or default).

<system.webServer>
   <security>
      <requestFiltering>
         <requestLimits maxUrl="10999" maxQueryString="9999" />
      </requestFiltering>
   </security>
</system.webServer>

http://msdn.microsoft.com/en-us/library/ms689462%28v=vs.90%29.aspx