See Error Code on dos

Often confused or frequent errors in executing an external command DOS? (eg chkdsk, xcopy, attrib, etc.)? Now do not anymore, because you can find what you're doing wrong. The trick on MS-​​DOS Prompt type COMMAND / Z. This command does not apply to internal commands such as copy, dir, rename, etc.. To return to MS-DOS mode "normal" you simply write the command EXIT COMMAND.