use Win32::File;
my $path="C:\\temp\\Perl\\TestFolder\\TestFile.txt";
my $attr;
Win32::File::GetAttributes($path, $attr);
if ($attr & COMPRESSED)
{
  print "File is compressed. Now uncompress it!\n";
  $attr &= ~COMPRESSED;
  Win32::File::SetAttributes($path, $attr);
}
else
{
  print "File is not compressed. Nothing to do here.\n";
}