Excel-Can't close 1 open Workbook without closing other open Workb

[Guest]

This concerns Excel 10(?). I have Office XP, but it is Office 10 in my
explorer files. Problem: I have a few opened Workbooks that I'm working on.
When I close one Workbook, it closes all open Workbooks at once. How do I
separate them and stop all these from closing at once? Has something changed
to the template--"Book1.xls"? If so, how do I correct that?

 

[Guest]

Are you clicking the X in the most upper-right corner? If so, that's closing
Excel as a whole, regardless of how many worksheets are open.

To close one, click on the X that is below the main one in the upper right
(in my Excel 2000 the secondary "X" is very close to the main "X").