Open
The Open 
(Ctrl+O) command enables you to open a File Comparison window or Directory Comparison window with the files or directories already selected. This is in contrast with the Compare Files and Compare Directories commands, which open empty comparison windows.
Note that the layout of the dialog box changes depending on whether you choose Compare files or Compare directories in the Mode group box.
Database data comparison files (*.dbdif) cannot be opened with this command, you have to use the Open Comparison File... command.