You can use <code> command to make your code show up properly... currently it looks like you are saying:

@header=H;
[download]

instead of:

@header=<H>;
[download]

This shouldn't even begin to work, at least as I understand perl.
You are also as noted above, never closing the H filehandle.
This won't really cause you any problems normally, but closing @header doesn't make any sense at all.
Of course I could be totally misinterpreting what you're trying to do.