You could put the main code into a seperate module - AddSignature
Then use the Workbook SheetChange event
Workbook Event code should be added to the workbook code module:
Copy the Excel VBA code that you want to use
Select the workbook in which you want to store the code
Hold the Alt key, and press the F11 key, to open the Visual Basic Editor
In the Project Explorer, find your workbook, and open the list of Microsoft Excel Objects
Right-click on the ThisWorkbook object, and choose View Code
Where the cursor is flashing, choose Edit | Paste
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