>Hi Fabio,
>
>I tried your suggestion, however, it did not solve the problem and I continue to get the error -- THIS can only be used within a method.
>
>I did some experiments and found out the behaviour I am getting is due to SET EXACT and/or SET ANSI settings. When I use SET EXACT ON or SET ANSI ON or == operator, the list box displays correct information. I am gettting the same behaviour in VFP 6 as well as VFP 9 on the same PC. I have confirmed that This.Value is not empty and its length is 6, same as Orders.Cust_ID. Here is the code I used in VALID() of combo box.
>
>

*!*	* Problem: Always extracts all records even though This.Value is not empty
>*!*	*          and LEN(This.value) = LEN(Orders.cust_ID)
>*!*	*  Form displays error: THIS can only be used within a method
>SET EXACT OFF
>SET ANSI OFF
>SELECT order_id,order_date, order_amt, shipped_on FROM orders ;
>    WHERE orders.cust_id = This.value ;
>    INTO CURSOR curSelectedOrders ;
>    ORDER BY order_id		
>
>* This works
>*!*	SET EXACT OFF
>*!*	SET ANSI OFF
>*!*	SELECT order_id,order_date, order_amt, shipped_on FROM orders ;
>*!*		INNER JOIN customer ON orders.cust_ID = customer.cust_ID ;
>*!*	    WHERE orders.cust_id = This.value ;
>*!*	    INTO CURSOR curSelectedOrders ;
>*!*	    ORDER BY order_id
>
>* This also works ...
>*!*	SET EXACT ON
>*!*	SET ANSI OFF
>*!*	SELECT order_id,order_date, order_amt, shipped_on FROM orders ;
>*!*	    WHERE orders.cust_id = This.value ;
>*!*	    INTO CURSOR curSelectedOrders ;
>*!*	    ORDER BY order_id		&& Extracts correct records
>
>
>* This also works
>*!*	SET EXACT OFF
>*!*	SET ANSI OFF
>*!*	SELECT order_id,order_date, order_amt, shipped_on FROM orders ;
>*!*	    WHERE orders.cust_id == This.value ;
>*!*	    INTO CURSOR curSelectedOrders ;
>*!*	    ORDER BY order_id		&& Extracts correct records
>
>* This also works
>*!*	SET EXACT OFF
>*!*	SET ANSI ON
>*!*	SELECT order_id,order_date, order_amt, shipped_on FROM orders ;
>*!*	    WHERE orders.cust_id = This.value ;
>*!*	    INTO CURSOR curSelectedOrders ;
>*!*	    ORDER BY order_id		&& Extracts correct records
>
>

>
>I looked at the help of SET EXACT and SET ANSI, but could not understand the reason for SELECT retruning all records, particularly the form displaying error.
>
>Has anyone seen something similar or any suggestions?

set exact it doesn't modify the operation of a SQL command

the error message ca to be wrong.