Report is not stable.

We are using fast-report ver 1.0.124 demo in one of our projects that we deployed on the web.

But the report page is not stable. Sometime it works well and shows the report.
We often get these errors:

Server Error in '/Teknoport' Application.

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Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
FastReport.Web.WebReport.qrlnKkeKj() +443
FastReport.Web.WebReport.OnLoad(EventArgs e) +65
System.Web.UI.Control.LoadRecursive() +47
System.Web.UI.Control.LoadRecursive() +131
System.Web.UI.Control.LoadRecursive() +131
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061



Server Error in '/Teknoport' Application.

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Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index]
System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource) +62
System.ThrowHelper.ThrowArgumentOutOfRangeException() +12
FastReport.Preview.PreparedPages.GetPage(Int32 index) +19
FastReport.Export.Html.HTMLExport.nUCCQ4jrt(Object ) +150
FastReport.Export.Html.HTMLExport.ProcessPage(Int32 p, Int32 ReportPage) +191
FastReport.Web.WebReport.JLvU2YhDe() +587
FastReport.Web.WebReport.RenderContents(HtmlTextWriter writer) +43
System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +29
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +130
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +24
System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +59
System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +68
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +37
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +130
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +24
System.Web.UI.Page.Render(HtmlTextWriter writer) +26
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1896


Also there are times that it generates only the 1st page, but the navigation buttons are not valid and it says "1 of 0 pages."


There were no such errors during the development of the project on our local system.

What is wrong here?