When I open a workbook (in Excel 2007) that contains a macro, I get the
following message every time:
The Visual Basic for Applications (VBA) macros in this workbook are
corrupted and have been deleted. The macro corruption most likely exists in
the current file. To recover the macros, open a backup copy of this file if
you have one.

However, I know that there isn't a corruption problem with the workbook
because I can take this same workbook and open it on another computer without
problem - and with the macros present and running fine. This has happened on
every workbook I have tried to open (that contains macros) - lots of them.
So it isn't a problem with a workbook - it is something on my computer. I
teach and I need to open and grade students' workbooks - and they contain
macros! So I don't know what to do! I would appreciate any suggestions you
can give.