The problem is that the WORKDAY function is in the Analysis Toolpak add-in,
and that counts as being in a different workbook. You may be better off
deriving a formula dependent on WEEKDAY.
--
David Biddulph

"nastech" wrote in message
...
hi, if this makes sense, item works in a cell, but does not within a
conditional format. error says cannot use data from a different
worksheet/book, which is not the case.

trying to hilite an item that is in spec of 3 days after date in A51.
thanks

=AND(ISNUMBER(A51),WORKDAY(A51,3)<=NOW())