The message doesn't make sense given that there is no column named "Customer" in the selection list. However, SIG357 is correct about needing a JOIN criteria. I also recommend using aliases to cut down the clutter and increase readability of the query. I also find queries easier to read and work with if I avoid spaces in names. Instead of [Sum Of UnitsMTD], I would use SumUnitsMTD or UnitsMTDSum.
SELECT
a.CustType,
Sum(b.UnitsMTD) AS [Sum Of UnitsMTD],
Sum(b.SalesMTD) AS [Sum Of SalesMTD],
Sum(b.CostMTD) AS [Sum Of CostMTD],
Sum(b.SalesPYTD) AS [Sum Of SalesPYTD],
Sum(b.CostPYTD) AS [Sum Of CostPYTD],
Sum(b.SalesYTD) AS [Sum Of SalesYTD],
Sum(b.CostYTD) AS [Sum Of CostYTD]
FROM Customer a Inner Join [Combined Sales By Customer] b
ON a.CustType=b.CustType
GROUP BY a.CustType;
Terry Broadbent
Please review faq183-874.
"The greatest obstacle to discovery is not ignorance -- it is the illusion of knowledge." - Daniel J Boorstin