Hide archived iterations and phases in Planned For widget

The "Planned For" drop-down on the Work Item shows archived iterations and phases. How do I prevent this widget from showing archived iterations and phases. I don't want to manually manipulate the database unless I know it's not going to cause corruption.
Currently this is really confusing to users as it shows about 20 items but only 4 are valid (not archived).
Currently this is really confusing to users as it shows about 20 items but only 4 are valid (not archived).