use strict;
use warnings;
use Win32::TieRegistry( Delimiter=>'/', ArrayValues=>0 );

my $mdb = 'c:/file.mdb';

sub find_MSAccess {
  my $key = 'HKEY_CLASSES_ROOT/Applications/MSACCESS.EXE/shell/Open/command//';
  my $pgm = $Registry->{$key} or die;
  # $pgm looks like '"C:\Program Files\Microsoft Office\OFFICE11\MSACCESS.EXE" /NOSTARTUP "%1"'
  $pgm =~ s{ \A " ( .*? MSACCESS\.EXE ) " .* \z }{$1}xi or die;
  return $pgm;
}

# Change a standard file path to DOS.
sub dos_path {
  local $_ = shift;
  tr{/}{\\};
  return $_;
}

my $access_pgm = find_MSAccess();
die "Can't run '$access_pgm'" unless -x $access_pgm;

my @cmd = (
  'start',
  $access_pgm, 
  dos_path($mdb),
);
system(@cmd)==0
  or die "System command failed!\nCommand was: '@cmd'\nError was: '$@'\n ";