You can enable or disable file name completion for a particular invocation of CMD.EXE with the /F:ON or /F:OFF switch. You ...

You can enable or disable file name completion for a particular invocation of CMD.EXE with the /F:ON or /F:OFF switch.  You can enable or disable completion for all invocations of CMD.EXE on a machine and/or user logon session by setting either or both of the following REG_DWORD values in the registry using REGEDIT.EXE:      HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\CompletionChar     HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\PathCompletionChar          and/or      HKEY_CURRENT_USER\Software\Microsoft\Command Processor\CompletionChar     HKEY_CURRENT_USER\Software\Microsoft\Command Processor\PathCompletionChar  with the hex value of a control character to use for a particular function (e.g.  0x4 is Ctrl-D and 0x6 is Ctrl-F).  The user specific settings take precedence over the machine settings.  The command line switches take precedence over the registry settings.  If completion is enabled with the /F:ON switch, the two control characters used are Ctrl-D for directory name completion and Ctrl-F for file name completion.  To disable a particular completion character in the registry, use the value for space (0x20) as it is not a valid control character.