Private Sub Workbook_Open()
your code or macro name here
End Sub
To access the Thisworkbook module, right-click on the Excel logo just left of
"File" on menu.
Select "View Code".
In dialog box drop-down at top left select Workbook and the Private Sub
Workbook_Open().........End Sub will be inserted.
Copy your macro code between the Open() and End Sub lines.
Or just enter the macro name, assuming the macro is in the same workbook.
If not in the same workbook, perhaps in Personal.xls or an Add-in, go to
Tools>References and checkmark the reference to use.
Save/Close and reopen.
Gord Dibben Excel MVP