The File | Close command closes the active window. If you have not saved the current changes, you are prompted to save changes before the window closes. You can also select the Close command by right-clicking an MDI tab at the top of the plot or worksheet window and clicking Close.
Click Yes to save changes and then close the window. If the file has not been previously saved the Save As dialog appears.
Click No to close the document without saving changes.
Click Cancel to return to the active document window.