Problem with File field in node when Ajax Poll enabled - solved.

There is bug in ajax_poll_form_alter function in ajax_poll.module file.

If you have Ajax Poll enabled, and you are on the node edit form page where is File field that you can't upload the file. There is wrong jquery.form.js loaded. Its system library and it should be done in the this way:

drupal_add_library('system', 'jquery.form');

instead (as is now):
$form['#attached']['js'][] = 'misc/jquery.form.js';