In case a file is in use by another application, Windows Explorer informs users to close the application and retry the file operation. Also, a new interface IFileIsInUse is introduced into the API which developers can use to let other applications switch to the main window of the application that has the file open or simply close the file from the "File in Use" dialog. If the running application exposes these operations by means of the IFileInUse interface, Windows Explorer, upon encountering a locked file, allows the user to close the file or switch to the application from the dialog box itself.