Yes, binmode is required for Windows, at least when I did this on W2K with IIS.

my $file = $req->param($inputfieldname);
my $fh = $req->upload($inputfieldname);
if (open(OUTFILE, ">$c{dir}{tmp}/$file")) {
  binmode(OUTFILE); # Windows only
  while (<$fh>) {
   print OUTFILE;
  }
  close (OUTFILE);
}
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