You would have to have a short piece of code for each checkbox to insert the current date. For example, assumming A1 has the checkbox number 1, then the code might be. . .
This would have to be repeated for CheckBox2 (for cell A2 & C2) etc.
A simpler idea may be to get users to double-click on the cell in column C when they've actioned that contact and then a short piece of code inserts the current date in that cell.
Right-click on the worksheet tab, select view code, and insert the following . . .
This avoids having to set up numerous checkboxes and associated code.
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