I import data from a different application into a .csv file, then save it as
an Excel workbook base.xls, using Excel 2000; that data is in correct sorted
order, column A runs from 00-00000 to 99-99999; there are about 230 items in
that series. Another workbook, calcu.xls uses the LOOKUP function to extract
data from the first workbook. Everything worked fine until we added 6 new
items in base.xls. Now those last six item Lookups in calcu.xls return a
blank space (not an error) instead of the actual item. When I use the Sort
menu to sort base.xls, the problem goes away, even though the actual sequence
of the data remains unchanged. If I change the formulas to VLOOKUP, they can
find the data in the original base.xls file. I'd like to avoid changing all
my LOOKUPs to VLOOKUPs, it would take quite awhile.