Hi, I am still having trouble with the "Insert" part.
I replicated your screenshot with sample tables and that worked - it gave me the non-duplicated records. When I added the first part with the Insert statement, it gives me the message "Syntax error in INSERT INTO statement". See below for what I used.
//(this part does not work)//
INSERT INTO unique values - all fields (Location, Item No, Description, Customer Name, Sum of Revenue, Total Quantity, Product Category, Customer Type)
//(this part below works fine)//
SELECT test.Month, test.Location, test.[Item No], test.Description, test.[Customer Name], test.[Sum of Revenue], test.[Total Quantity], test.[Product Category], test.[Customer Type], [unique values - all fields].Month, [unique values - all fields].Location, [unique values - all fields].[Item No], [unique values - all fields].Description, [unique values - all fields].[Customer Name], [unique values - all fields].[Sum of Revenue], [unique values - all fields].[Total Quantity], [unique values - all fields].[Product Category], [unique values - all fields].[Customer Type]
FROM test LEFT JOIN [unique values - all fields] ON (test.Month = [unique values - all fields].Month) AND (test.Location = [unique values - all fields].Location) AND (test.[Item No] = [unique values - all fields].[Item No]) AND (test.Description = [unique values - all fields].Description) AND (test.[Customer Name] = [unique values - all fields].[Customer Name]) AND (test.[Sum of Revenue] = [unique values - all fields].[Sum of Revenue]) AND (test.[Total Quantity] = [unique values - all fields].[Total Quantity]) AND (test.[Product Category] = [unique values - all fields].[Product Category]) AND (test.[Customer Type] = [unique values - all fields].[Customer Type])
WHERE ((([unique values - all fields].Location) Is Null) AND (([unique values - all fields].[Item No]) Is Null) AND (([unique values - all fields].Description) Is Null) AND (([unique values - all fields].[Customer Name]) Is Null) AND (([unique values - all fields].[Sum of Revenue]) Is Null) AND (([unique values - all fields].[Total Quantity]) Is Null) AND (([unique values - all fields].[Product Category]) Is Null) AND (([unique values - all fields].[Customer Type]) Is Null));