I recently purchased a new MacBook Pro (I also have a Windows Desktop). Since I subscribe to Microsoft office, I downloaded all those applications to the new computer. I have a number of Excel workbooks with multiple sheets that open when I open the workbook, and I expect that they all will close when I try to close the workbook. But on the MacBook Pro, executing File, Close only closes the active sheet, leaving the rest open. I don't know for sure whether this was always the case, or whether I inadvertently did something to cause the workbooks to behave this way. I note that the drop-down list obtained when clicking on "Window" in the toolbar shows the workbook sheets, some with a black dot to the left of the sheet name and some without the black dot. I do not know what the dots mean, and looking through preferences, I don't see anything that helps me with this issue.