When Access says "#NAME", its telling you it doesn't recognize the name you
gave it. Typically this is because the name of the form or the name of the
control isn't recognized.

I'd look first at Format([X!Date of X] ... is "X" a table name or a form
name?

Regards

Jeff Boyce
Microsoft Office/Access MVP

"tm3025" wrote in message
...
I entered the following expression into the control source of an unbound
text
box on a form. The form was created from a personal info table which DOB
came
from, but Date of X came from a different table. When I try to enter this
it,
all I get in the text box is #NAME?

=DateDiff("yyyy", [DOB], Surgery![Date of
X])-IIF(Format([DOB],"mmdd")Format([X!Date of X],"mmdd"),1,0)

My first attempt at this involved a query with the same expression, and it
returned correct values. However, when I made the field from the query the
control source of the text box in the form, it also returned #NAME?

I'm guessing there must be something wrong in the way I am going about
this.
Any help would be much appreciated.