You guessed right. I am very busy at the moment and it is about 7 years since
I used OnTime. I would need to research the closing of the schedule. I would
have thought that closing the workbook would kill the schedule, but that may
not be the case.

In your autoopen you do not set dTime. Therefore if you close before the
first run of autosavmacro there will be no dtime for the before close macro  to
find (or it will have a value different from the value of the onTime process
you are trying to kill)