OK, it isn't supported:

http://support.microsoft.com/default...23&Product=xlw
XL97: Cannot Use Custom Function with Data Validation

I suspect this hasn't changed in later versions.

--
Regards,
Tom Ogilvy


"Tom Ogilvy" wrote in message
...
I can reproduce it, but I haven't figured out the cause.

--
Regards,
Tom Ogilvy

"Alex@JPCS" wrote in message
...
Tom,



I am using:



Function ID_Frontlog(projno) As Boolean

ID_Frontlog = False

On Error GoTo XIT

If Right(projno, 2) = " F" Or _

Right(projno, 2) = " P" Or _

Right(projno, 2) = " E" Then

ID_Frontlog = True

End If



XIT:

End Function

This function works in code, and works when entered as a formula
directly
on
the sheet.

I am trying to set the custom validation Formula in the validation
dialog
(not via VBA) as:

=ID_Frontlog(B9)

where B9 contains the text value "00OLE001 F". The error message is:

"A named range you specified cannot be found"



I know that it is easy enough to put the conditions directly into the
validation, however since the ID_Frontlog function is also used for
other
verification in my VBA routines, the attraction is to only have to
update
conditions in the function once, rather than going to the sheet.

Your advice would be greatly appreciated.

Alex


"Tom Ogilvy" wrote in message
...
=myFunction

is a user defined name

=myFunction()

is a function

Is that your problem?

--
Regards,
Tom Ogilvy

"Alex J" wrote in message
...
All,
I am trying to use a user defined function in the validation for a
cell
range. The validation type is custom, and I have a function which is
defined
as Boolean.

I get an error message saying that the referenced named range is
invalid.
I
am not using a named range!

Should user defined functions work in validation?

Thanks,
Alex J