I have a ZIP archive for download (archive.zip).
- Your plugin adds PHP errors on top of a ZIP download file like so, which makes the ZIP archive corrupt:
<br /> <b>Warning</b>: fseek() [<a href='function.fseek'>function.fseek</a>]: stream does not support seeking in <b>/home/flag/public_html/cmswp/wp-content/plugins/email-before-download/download.php</b> on line <b>225</b><br />
- If I manually removed the lines in a text/hex/binary editor, the ZIP archive worked just find.
So your plugin seems to redirect any error "stderr" to the download stream.