Answers.Body: <p>This seems to be an issue with 4.7 and 4.7.1:
  <a href="https://issues.civicrm.org/jira/browse/CRM-17953" rel="nofollow">https://issues.civicrm.org/jira/browse/CRM-17953</a></p>
  
  <p>The issue has a workaround solution, and the full fix will be linked from that issue when it has been implemented.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-02-03T13:30:14.123Z
Answers.LastActivityDate: 2016-02-03T14:41:52.010Z
Answers.LastEditDate: 2016-02-03T14:41:52.010Z
Answers.UserDisplayName: John
Body: <p>We have recently upgraded to CiviCRM 4.7.0, and we have Drupal 7.41</p>
  
  <p>As part of the upgrade process, I upgraded PHP to 5.6.17</p>
  
  <p>Most things work brilliantly, but when we have link tracking enabled on a CiviMail email we get this error:</p>
  
  <blockquote>
    <p>Fatal error: Call to undefined function drupal_add_http_header() in
    /home/ace/public_html/sites/all/modules/civicrm/CRM/Utils/System/Drupal.php
    on line 789</p>
  </blockquote>
  
  <p>An example URL is <a href="https://acenterprises.org.uk/sites/all/modules/civicrm/extern/url.php?u=1535&amp;qid=864040" rel="nofollow">https://acenterprises.org.uk/sites/all/modules/civicrm/extern/url.php?u=1535&amp;qid=864040</a></p>
  
  <p>There's nothing recorded in the HTTP Error Log - can anyone give me any clues on debugging this error?</p>
  
  <p>Thanks!</p>
  
Tags: <civimail><upgrade>
Title: CiviMail - Error 500 when tracking clickthroughs
ThreadText: # CiviMail - Error 500 when tracking clickthroughs
  
  (Asked by: username_0 on 2016-02-02)
  
  We have recently upgraded to CiviCRM 4.7.0, and we have Drupal 7.41
  
  As part of the upgrade process, I upgraded PHP to 5.6.17
  
  Most things work brilliantly, but when we have link tracking enabled on a CiviMail email we get this error:
  
  > Fatal error: Call to undefined function drupal\_add\_http\_header() in
  > /home/ace/public\_html/sites/all/modules/civicrm/CRM/Utils/System/Drupal.php
  > on line 789
  
  An example URL is <https://acenterprises.org.uk/sites/all/modules/civicrm/extern/url.php?u=1535&qid=864040>
  
  There's nothing recorded in the HTTP Error Log - can anyone give me any clues on debugging this error?
  
  Thanks!
  
  **Tags:** civimail, upgrade
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2016-02-03. Score: 2 | Accepted answer
  
  This seems to be an issue with 4.7 and 4.7.1:
  <https://issues.civicrm.org/jira/browse/CRM-17953>
  
  The issue has a workaround solution, and the full fix will be linked from that issue when it has been implemented.
  
  
  ---
  
  