Forces the FAT file structure to be validated. It is implicitly
    done if the version of EFI$CP used to create the volume is out-
    of-date. Unless the /NOCHECK qualifier is used - which will
    prevent all checking. Older versions of EFI$CP got the file
    lengths wrong. It also screwed up the RENAME operation on files
    (leaving a stale file with 0 length). The /CHECK option does
    essentially what EFICHK will do from the EFI shell.

    Use /NOCHECK or /WRITELOCK if you are concerned about changing
    the contents.