Wild guess (based on comparing your code to my upload code). Instead of 
  ## pull the file in a variable
  my $fh = $query->upload('upload');

  ## determine the file type via the headers
  my $type = $query->uploadInfo($fh)->{'Content-Type'};

[download]
try 
  ## pull the filename in a variable
  my $fname = $query->param('upload');

  ## determine the file type via the headers
  my $info = $query->uploadInfo($fname);
  my $type = $info->{'Content-Type'};

[download]
I take an extra step, but found that having $info where I could get at it with the debugger paid off (once, which was enough).

In reply to Re: using uploadInfo from CGI.pm by dws
in thread using uploadInfo from CGI.pm by c

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