Error during serialization or deserialization using the JSON JavaScriptSerializer

Hi, when I click activities on Social Pane in CRM 2013 on premises. I got the error as the topics.

Does anyone know what is this error and have any idea to solve ?

Thank you very much,

This is the full error log:

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MSCRM Error Report:

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Error: System.InvalidOperationException: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.

  at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat)

  at Microsoft.Crm.Application.Platform.Grid.GridDataProviderBase.PrepareJsonSerializedGridData(StringBuilder sbData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.Refresh(String gridXml, StringBuilder sbXml, StringBuilder sbHtml, Boolean returnJsonData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.ProcessRequestInternal(HttpContext context)

Error Message: System.InvalidOperationException: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.

  at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat)

  at Microsoft.Crm.Application.Platform.Grid.GridDataProviderBase.PrepareJsonSerializedGridData(StringBuilder sbData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.Refresh(String gridXml, StringBuilder sbXml, StringBuilder sbHtml, Boolean returnJsonData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.ProcessRequestInternal(HttpContext context)

Source File: Not available

Line Number: Not available

Request URL: http://org:5555/org/AppWebServices/AppGridWebService.ashx?operation=RefreshData

Stack Trace Info: [InvalidOperationException: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.]

  at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat)

  at Microsoft.Crm.Application.Platform.Grid.GridDataProviderBase.PrepareJsonSerializedGridData(StringBuilder sbData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.Refresh(String gridXml, StringBuilder sbXml, StringBuilder sbHtml, Boolean returnJsonData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.ProcessRequestInternal(HttpContext context)

[XmlException: System.InvalidOperationException: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.   at System.Web.Script.Serialization.JavaScriptSerializer.Serialize(Object obj, StringBuilder output, SerializationFormat serializationFormat)

  at Microsoft.Crm.Application.Platform.Grid.GridDataProviderBase.PrepareJsonSerializedGridData(StringBuilder sbData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.Refresh(String gridXml, StringBuilder sbXml, StringBuilder sbHtml, Boolean returnJsonData)

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.ProcessRequestInternal(HttpContext context)]

  at Microsoft.Crm.Application.WebServices.AppGridWebServiceHandler.ProcessRequestInternal(HttpContext context)

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