Forget wrapping @YDayNo. What was I thinking?
It would be simpler to store the date/time in CTime format and then use the FlipCTime() UDF that Bryce mentioned. Just convert 45 days to seconds (3888000) and Bob's your uncle.

So basically write the CTime to the reg when the app is run and then run it again if the reg value + 3888000 >= now in CTime.
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