Durward wrote concerning a problem he was having with calculation settings in his Excel. He indicated that according to all he had read, the calculation setting for Excel (Manual or Automatic) defaults to Automatic. Yet somehow, when Durward opens a new workbook, the calculation setting is set to Manual. This happens on his work system as well as his home system. He wonders if there a way to reset the calculation setting back to Automatic.

Testing has shown that the calculation setting is set to Automatic by default. It will only be set to Manual if (1) you have changed the default workbook to one that has the calculation mode set to Manual; (2) if there is some sort of AutoOpen macro that sets the calculation mode; (3) if you have some automatically loading workbooks (XLSX or XLTX, including the Personal workbook) that have calculation set to Manual; or (4) if you start Excel by double-clicking, in Windows, on a workbook that has calculation set to Manual.

Note, especially, conditions 3 and 4. Excel may very well be starting with the calculation mode set to Automatic, but it is overridden by the setting within the file that is first opened. If that workbook has calculation mode set to Manual, then Excel presumes you want Manual as your default calculation mode for that session. The only solution to this problem is to open those workbooks, change the calculation mode in them, save them, and restart Excel.

The other option is to add an AutoOpen macro to any of your workbooks that absolutely must be opened with calculation mode set to Automatic, no matter what. This can be a simple macro, such as the following:

Private Sub Workbook_Open()
    Application.Calculation = xlCalculationAutomatic
End Sub