Yep, that was it. It now says "Customer is not unique", so I have to fix that now.
Thanks Beth,

>Hi Cecil,

>PMFJI, but with the error you get and what I see, the problem may be with your On string. Try,

...
> LEFT JOIN StandsIn si ON si.cust = cs.custno ;
LEFT JOIN Stands_Out so ON so.cust = cs.custno ;