Reporting: he sum in the status bar (bottom right) Open Office Calc is incorrect.

This warning is not really an error but just a different behavior of Open Office Calc to Microsoft Office Excel.

In Calc when you select the cells to see the amount from the status bar (bottom right) if the application takes into account other worksheets are selected, and then also their sum corresponding cells. This does not happen in Excel and some will see an error on Open Office Calc.

To the uninitiated it is in Open Office Calc and Microsoft Office Excel, you can select multiple worksheets by holding down the Ctrl key and clicking on the sheets you want, so writing on a single sheet editing is performed on all selected sheets.

To remove the selection again just hold down the Ctrl key and click on one sheet.