SAP System Message: Work process restarted; session terminated

Hi ,

when iam executing the standard report SAPMZPAD after executing this report ,when i try to click on "Pricelist Exception" session terminates

and below pop up appears .

" SAP System Message: Work process restarted; session terminated"

what will be cause of this error ......

can any one provide me hint why this error occurs ....

Thanks ,

vinay.