rodvaN,
As far as I know, the check box that you see in the QBE window is not a property that can be manipulated through code. That check box is there to tell the Access compilier how to render the SQL statement when the user has completed designing the query. When the "Show" is checked, this says to include that field in the field list in the SQL statement. When it is not checked then the field is either left completely out of the SQL statement or if there is criteria for that field, then that field is included in the WHERE part of the SQL statement. If that field is just being used to specify the sort order then that field would only be included in the ORDER By statement in the SQL statement.
With all that said, as llkhoutx said, you can use a different sql statment that excludes the field(s) you do not want to see. You can then swap out the SQL statements when the user clicks a checkbox if you like.
HTH
