Question : sql error 536

i have following query and getting sql error 536
how can i resolve it

Thanks

SELECT    tbo.or_date AS [Date],tbm.account as Account,tbo.or_no AS [Order No],Left(tbo.or_itemname,len(tbo.or_itemname)-5) AS [Aile],tbo.or_itemname AS [Price], tbo.or_paytype AS [PayType]
FROM             tblOrder tbo INNER JOIN
                      tblMember tbm ON tbo.save_number = tbm.save_number
where tbo.or_status=1 and or_no LIKE 'XXX%'

Answer : sql error 536

Actually, this appears to the be the correct SQL:
   ISNULL(MAX(CAST(SUBSTRING(chainlink, 6, 6) AS int)), 0)