Can I set an unlimited length for maxJsonLength in web.config?

The MaxJsonLength property cannot be unlimited, is an integer property that defaults to 102400 (100k).

You can set the MaxJsonLength property on your web.config:

<configuration> 

   <system.web.extensions>

       <scripting>

           <webServices>

               <jsonSerialization maxJsonLength="50000000"/>

           </webServices>

       </scripting>

   </system.web.extensions>

</configuration>