Instead of:
IF MCARD_NBR<>Card_Nbr .OR. DELETE()

Use:
IF (MCARD_NBR<>Card_Nbr .OR. DELETE()) .AND. !EMPTY(MCARD_NBR)

and then if they leave it blank, they can get out of the field.

>>Why not put this in the mytextbox1.VALID instead?
>>
>>store allt(this.value) to mcard_nbr
>>SEEK MCARD_NBR
>>IF MCARD_NBR<>Card_Nbr .OR. DELETE()
>> DO quickmsg WITH "CUSTOMER'S CARD NO. NOT ON FILE"
>> RETURN 0
>>ENDIF
>
>what happens when the user does NOT know a correct card #? It will loop forever and hitting the quit cmdbutton doesn't quit.