Hi Colin
Try changing to
=IF(COUNTA(Mydata)<12,"DATA!!!",SUM(Mydata))
Then apply conditional formatting to cell
Formula Is =NOT(ISNUMBER(cellref)) where cellref is the cell where your
formula is entered
Format Font RED, Bold

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Regards

Roger Govier


"Colinhp" wrote in message
...
Hi,

The nominated cell for the error data is too small for the user to
see. Is
there a simple solution to having a message box appear when the If
function
returns the message? I have posted this question in the Excel
programming
section, prior to me reading your second response. Data Validation
appears
not to work as the cell is not selected by the user.

"Max" wrote:

"Roger Govier" wrote:
.. =IF(COUNTA(Mydata)<12,"You need more data",SUM(Mydata))

Nice, neat solution, Roger !
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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