Access headache?

Question

Ok, I'll try you guys. Why does the following work but not othere (in a query)?
Works = IIf([Expr12] Is Null,[Origin],[Expr12])

Does not work = IIf([Destination]=[STN CD],[Profit Center])

or iif( [Destination] = [All Stations]![STN CD], [All Stations]![Profit Center] )

Sorry everone, these is one that is giving problems:
IIf([Expr10]=[STN CD],[Profit Center])

Thanks K, but did not work ether.

Should this work?

IIf([Expr10]=[All Stations]![STN CD],[All Stations]![STN CD],[Expr10])

Answer 1

IIF needs THREE fields, not two.

Works = IIf([Expr12] Is Null,[Origin],[Expr12])
field 1= [Expr12] Is Null
field 2= [Origin]
field 3=[Expr12]

Your other two expressions lacks field 3.

EDIT: The new expression should work. (or at least not give you an error) What answer did you get? Why was it not what you were expecting? Add two clumns to view the intermediate numbers and you should see why immediately.