Getting #Error in report field

I'm Getting #Error in some report fields (not all), the field does exist in the source query.
Here is my control source:

=IIf(NZ([email],"")="","No Data",[email])

The odd thing is if I put a hidden field on the screen callex txtEmail with a control source of Email and put txtEmail in the above control source, it works ?!?

I am confused !

Don't be confused. In reports, if you wish to use a field's value when the
field is in the report's recordsource, you must do one of the following
items (from post by Marshall Barton, MVP, this morning):

"...if you want to refer to a field in the report's
record source, you also need to use it in a detail section
control's ControlSource, either as a bound field or in an
expression. This somewhat annoying requirement is because
of an Access optimazation where reports (unlike forms) do
not waste time retrieving fields that it thinks are not
used."


--
Ken Snell
MS ACCESS MVP


"David" wrote in message
...
I'm Getting #Error in some report fields (not all), the field does exist
in the source query.
Here is my control source:

=IIf(NZ([email],"")="","No Data",[email])

The odd thing is if I put a hidden field on the screen callex txtEmail
with a control source of Email and put txtEmail in the above control source,
it works ?!?

I am confused !