Hi all! I tryed to convert a powerpivot from excel 2010 to 2013. I've delete all excel sheets which contains pivot tables and graphics. At this point, the refresh of the data (sql db, linked excel tables) works prober. Then I've rebuilded the excel sheets which contains the data of the powerpivot datamodel. As long as I've less then 5 Excel sheets it works prober. But if I add more sheets, I cannot refresh my data. In the excel sheet I see the message "data will be readed" (daten werden gelesen in German ). Is there a limit of sheets or tables? On every sheet I've two pivot tables and one or two charts. In Excel 2010 it works proper... Can anybody help? Sorry, for my bad english! Regards, Vikinger