The report document has already been closed.

Hi experts,

I have a web application which uses Crystal Reports to display some charts. I'm using the part viewer in order to import in my web application only the chart. It's working ok but after some period of time when the browser is open when I refresh the page I get the following error:

com.crystaldecisions.sdk.occa.report.lib.ReportSDKException: The report document has already been closed.---- Error code:-2147467259 Error code name:failed 

Can you tell me what could be the reason for that and how to fix it? Am I missing some configuration or something is expiring?

Best regards,

Martin