When a user tries to save or preview a query, they receive the following error: Important Notice! You tried to save a query which has a circular dependency.
A circular dependency error happens when you choose the same query for the Starting Criteria as you are working on.
When you receive the error in eTapestry choose the blue link "continue to use eTapestry" . This will return you to the "Edit Query Definition" screen. Change the starting criteria to Base / All Constituents or another query other than the query you are editing.