Drupal 7 commons AJAX bulk operations active queue error Drupal 7 commons site with private trusted contacts enabled. When the accept trusted contact or break contact button is clicked this error appears.
An error has occurred.
Please continue to the error page

An AJAX HTTP error occurred. HTTP Result Code: 500 Debugging information follows. Path: /en/batch?id=6305&amp;op=do StatusText: Service unavailable (with message) ResponseText:
ERROR PAGE - An error occurred while processing views_bulk_operations_active_queue_process with arguments: views_bulk_operations_active_queue_process
I have tried searching and this error seems quite wide with no results. 
How do I resolve this?
For me, this error was due to the PHP version being used (5.3). Using PHP 5.4+ resolved it. You may also want to look at https://www.drupal.org/node/1871702 if the PHP version isn't your issue.