Error 3122 tried to execute a query that does not include specified expression (1 Viewer)

[Andre Webster]

I created a calculated field in one my my queries. below is the formula, but i received this error message.
( Error 3122 - Tried to execute a query that does not include the specified expression )

Formula:
Related Transfers: IIf([Start date]>=([2011_to_2012_Transfers]![ship_date]) And [End Date]<=([2011_to_2012_Transfers]![ship_date]),Sum([2011_to_2012_Transfers]![Qty]),0)

 

[Andre Webster]

Can anyone shed some light and point me in the right direction? thanks