Event registrations hang for all events and then gives error whenever "send email confirmation" is set to "yes". While it's hanging, I can see the registration went through, then it finally shows an error with "Could not find valid value for id". I posted the full error at the end of this post.
I tried Amazon SES and sendgrid, getting the same error either way. Either way, sending test emails from outbound email settings works. It just gets stuck sending the email confirmation when registering events.
I'm currently using Drupal 7.37 and CiviCRM 4.6.3.
Full error:
#0 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Error.php(359): CRM_Core_Error::backtrace()
#1 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Utils/Request.php(95): CRM_Core_Error::fatal("Could not find valid value for id")
#2 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Event/Form/Registration.php(183): CRM_Utils_Request::retrieve("id", "Positive", Object(CRM_Event_Form_Registration_Register), TRUE)
#3 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Event/Form/Registration/Register.php(88): CRM_Event_Form_Registration->preProcess()
#4 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Form.php(455): CRM_Event_Form_Registration_Register->preProcess()
#5 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/QuickForm/Action/Display.php(94): CRM_Core_Form->buildForm()
#6 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/packages/HTML/QuickForm/Controller.php(203): CRM_Core_QuickForm_Action_Display->perform(Object(CRM_Event_Form_Registration_Register), "display")
#7 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/packages/HTML/QuickForm/Page.php(103): HTML_QuickForm_Controller->handle(Object(CRM_Event_Form_Registration_Register), "display")
#8 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Controller.php(353): HTML_QuickForm_Page->handle("display")
#9 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Invoke.php(312): CRM_Core_Controller->run((Array:3), NULL)
#10 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Invoke.php(86): CRM_Core_Invoke::runItem((Array:15))
#11 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/CRM/Core/Invoke.php(54): CRM_Core_Invoke::_invoke((Array:3))
#12 /opt/bitnami/apps/drupal/htdocs/sites/all/modules/civicrm/drupal/civicrm.module(489): CRM_Core_Invoke::invoke((Array:3))
#13 [internal function](): civicrm_invoke("event", "register")
#14 /opt/bitnami/apps/drupal/htdocs/includes/menu.inc(519): call_user_func_array("civicrm_invoke", (Array:2))
#15 /opt/bitnami/apps/drupal/htdocs/index.php(21): menu_execute_active_handler()
#16 {main}