Hi,
One way. I'm assuming there are several different dates in your column and you want the email sent if the latest date in the list is more than 21 days ago.
So introduce a cell named "CheckDate" and in this cell enter the formula:
=MAX(A:A)
assuming column A is the one containing the dates.
Then create a module level macro as follows
Then decide what event you want to use to trigger the macro. If you want this to run the in the Workbook open event add a line of code
Call CheckDate21
If you want to run this at any time then create a button and attach the macro to the button.
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