Applies to: SharePoint On-Premises

Question:- How to increase maxJsonLength property to its maximum value for a SharePoint Web application?

Steps:-

– Go to "C:\inetpub\wwwroot\wss\VirtualDirectories" folder in the SharePoint server.

– Open corresponding folder of the web application for which this property should be modified.

– Edit web.config file and update value of maxJsonLength property to "2147483647". Add an extension like shown below and increase the value if the property isn’t available.

<system.web.extensions>
    <scripting>
      <webServices>
        <jsonSerialization maxJsonLength="2147483647" />
      </webServices>
    </scripting>
  </system.web.extensions>

Note:

1. Repeat this in all the SharePoint servers in case of a multi-server Farm.

2. Take a copy of original web.config file before making any changes as a safety backup.