I'm getting the message "Operation must use an updatable query."

This error occurs when the current query's Update To row includes a field from either a crosstab query or select query in which an aggregate (total) was calculated for the field (using either the Totals row or a domain function in the Field row). To update a field using the aggregate of another field, calculate the aggregate in the update query itself, not a different query.

1. In query Design view for the current query, remove the field you added from the crosstab or select query (where an aggregate was calculated for the field).
   
   
2. In the Update To cell of the field you want to update, enter a domain function that calculates the same aggregate as is calculated for that field in the select or crosstab query.

   For example, if you had a calculated field named Sales So Far in your Products table, you could update it with the product of the Quantity and UnitPrice fields in the Order Details table by adding it to the design grid in the update query and then entering the following domain function in its Update To cell.

   DSum("[Quantity]*[UnitPrice]","Order Details","[ProductID]=" & [ProductID])

3. To run the query, click Run on the toolbar.
   
   
4. To see the results, open the table by clicking Tables under Objects in the Database window and clicking Open on the Database window toolbar.