Unsupported Operation. A document processed by the JRC engine cannot be opened in the C++ stack (Build Action is "Content"))

I have a crystal report developed in VS-2015 and is hosted as a Web application in IIS Server.

The reports work perfectly fine for a short period of time, and after few minutes this error start appearing on client browsers:

[COMException (0x80041811): Unsupported Operation. A document processed by the JRC engine cannot be opened in the C++ stack.] CrystalDecisions.ReportAppServer.ClientDoc.ReportClientDocumentClass.Open(Object& DocumentPath, Int32 Options) +0 CrystalDecisions.ReportAppServer.ReportClientDocumentWrapper.Open(Object& DocumentPath, Int32 Options) +90 CrystalDecisions.ReportAppServer.ReportClientDocumentWrapper.EnsureDocumentIsOpened() +258

[CrystalReportsException: Load report failed.] CMS.COD.CustomerPortalNT.CustomerLoadsheet.btnPrintReport_Click(Object sender, EventArgs e) in E:\Office Sources\COD PORTALS\CMS.COD.CustomerPortal\CMS.COD.CustomerPortal\CMS.COD.CustomerPortalNT\CustomerLoadsheet.aspx.cs:411 System.Web.UI.WebControls.Button.OnClick(EventArgs e) +9628114 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +103 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +35 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1724

However this error goes once I restart my IIS Server. I have tried many solutions posted here before, but none of them works.

Here is my code to download the crystal report (Server code):

DataTable dataTable = (DataTable)Session["DT"];
ReportDocument crystalReport = new ReportDocument();
crystalReport.Load(Server.MapPath("~/XRPT/rptLoadSheetPrint.rpt"));
crystalReport.SetDataSource(dataTable);                          

crystalReport.ExportToHttpResponse(CrystalDecisions.Shared.ExportFormatType.PortableDocFormat, Response, true, "PersonDetails");
crystalReport.Close();
crystalReport.Dispose();

I have already tried following things but all in vain:

1. Compile report with Build Action as "Content".
2. Checked all the permissions of the report file on server.
3. Increasing the worker print limit using registry editor.

Can anyone help me what could be the problem?