By definition it should NOT be updateable ... Think about it: you're aggregating values in a value THAT IS NOT UNIQUELY IDENTIFIABLE BECAUSE IT IS NOT PART OF ANY TABLE and as such your update query will not work because it REQUIRES JUST THAT ATTRIBUTE: A UNIQUE WAY TO IDENTIFY THE ROW TO UPDATE AND THE ROW FROM WHICH THE UPDATE GETS ITS VALUE. Now, this IS trivial using VBA ... Gen your query to get the result to update with. Gen the update query on the table and row with that value. Execute. Done.