Problem with expression using IIF() and ISNOTHING()

Can anyone tell me what is wrong with these expression?  Looks alright to me but SSRS 2008R2 throws an error saying "expression required".\

=IIF( IsNothing(Fields!SHIPMENT_DATE.Value), '', FormatDateTime(Fields!SHIPMENT_DATE.Value, DateFormat.ShortDate) )

Then I tried then I tried this.

=IIF( IsNothing(Fields!SHIPMENT_DATE.Value), '', CStr(FormatDateTime(Fields!SHIPMENT_DATE.Value, DateFormat.ShortDate)) )

Neither worked.

This link looks like it answered the question but all I see in the code blocks is scroll bars and no code.



This is kind of high priority as without this FormatDateTime converts nulls into 1/1/0001

Edward R. Joell MCSD MCDBA