np,
Assuming that you are editing on a form and not grid edit or some other kind if input method, just create a Dynamic form rule to say.
When multiple conditions are true.
When all of
[My date field] is (leave empty)
[My checkbox field is checked
Action
Change the value of [My date field] to (and there should be a drop down choice for the current date)
Note that there is a checkbox at he very bottom of the setup page. Select which setting is what you want.
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Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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