Closing a named document

The application I am working on is an MDI which allows the user to switch between several pages. When a new page is loaded the current document is closed and then the new document is opened. Unfortunately this causes flicker, and if an error occurs in opening the new document I am left with an empty one. What I want to do is open a new document and then close the previous one - but sending an ID_FILE_CLOSE message to the MainFrame will cause the current document to be closed not the previous one. How can I close this previous document without touching the current one?