Hi

you can't do it via data / validation - as this only works when someone
enters something into the cell - you could however, put code against a
worksheet_selectionchange, workbook_beforeprint or workbook_beforeclose
event - which ever is the most appropriate that doesn't let them select
another sheet / print or close the workbook without data in a specific
place.
If you'ld like additional information on how to this, please nominate an
event and the cell(s) you want to check.

Cheers
JulieD

"Spyder" wrote in message
...
Is it possible to add validation to a cell such that if it is null an
error/warning message appears? The cell should allow any value to be
entered, it just can't be null.

Thanks!