Source : Free On-Line Dictionary of Computing

Blue Screen of Life
     
         (BSOL, by analogy with "{Blue Screen of
        Death}") The opening screen of {Microsoft} {Windows NT}.
     
        This screen shows the {file system} loading, and any problems
        such as conversions from {FAT} to {NTFS} or a scan of a {hard
        drive}.
     
        The Blue Screen of Life occurs in one way, as opposed to the
        {Blue Screen of Death}, which can occur in many different ways
        and times.
     
        [Is this term ever used in connection with {Windows 3.x} or
        {Windows 9x}?]
     
        (1999-04-18)