I have a WB created and saved in Excel 2003 format. I use and edit the file
in Excel 2007 in compatibility mode at times. I need to keep it in 2003
format because some users are still on Excel 2003 and some are on 2007.

The WS are protected and have formulas and complex formatting and macros in
the WB. Sometimes in 2007, when I save it I get the Compatibilty error report
that points to certain cells ranges on the worksheets with this message:

This workbook contains data in cells outside of the row and column limit of
the selected file format. Data beyond 256 (IV) columns by 65,536 rows will
not be saved. Formula references to data in this region will return a #REF!
error.

One way I can cause this is to create a new blank ws. The cells called out
as having a compatibility problem have validation on a list. The list is a
dependent list with the following validation formula:

=OFFSET(INDIRECT(VLOOKUP(F13,LookupList,2,0)),0,0, COUNTA(INDIRECT(VLOOKUP(F13,LookupList,2,0)&"List" )),1)

The VLOOKUP is pulling the Named Range from a lookup list to get the name of
the dependent list. The formula is built this way so that the drop down only
picks up the list cells that have data and ignores the blank cells at the
bottom of the named list range. F13 contains the value we want to find in the
lookuplist table.

Any ideas why this formula would trigger the compatibility warning? If I
save the file anyway, the warning is gone the next time I open and save the
file.

Thanks,
John