From the Migrations page, you can delete migrations. To delete:

1. Select a migration (row) to delete
   
2. Click the Delete Migration button on the toolbar
   
   1. The delete button is only visible when Enable Delete has been checked under Settings–Options (top right corner of the UI)
      
      
   2. The delete button is enabled (ungrayed out) when a migration (row) is selected
      
      
   3. The delete function is only available to users in the Administrator security group
3. Click the Delete button to confirm the delete operation. Click the Cancel button to cancel the operation.
   

NOTE: Only migrations in the Not Started status can be deleted.