Webform file upload not working after hook_from_alter I have used the following form alter to do some adjustments to my form but after the file upload stops working. I cant seem to find out why. This is the module code.

Any help would be much appreciated.

if ($form_id == 'webform_client_form_3'){
    //image btn
    $form['actions']['submit']['#type'] = 'image_button';   
    $form['actions']['submit']['#src'] = drupal_get_path('theme', 'MY_THEME').'/images/submit2.png';
    $form['actions']['submit']['#attributes']['name'][] = 'op'; 

    //palceholders
    $form['submitted']['forename']['#attributes']['placeholder'] = t('Forename'); 
    $form['submitted']['surname']['#attributes']['placeholder'] = t('Surname'); 
    $form['submitted']['post_code']['#attributes']['placeholder'] = t('Post Code'); 

}
I fixed this by forcing the the 'op' value to

 $form['actions']['op'] = array( '#type' =&gt; 'value', '#value' =&gt; 'Submit', );