I am having the same issue. It happened right after I updated Joomla to 3.5.1. The error of "0 invalid address" happens when a user logins from the front end and in the admin. Researching on this error always bring be to HikaShop.
An error has occurred.
0 Invalid address:
Call stack
# Function Location
1 JApplicationCms->execute() /var/www/html/joomla/administrator/index.php:51
2 JApplicationAdministrator->doExecute() /var/www/html/joomla/libraries/cms/application/cms.php:257
3 JApplicationAdministrator->dispatch() /var/www/html/joomla/libraries/cms/application/administrator.php:152
4 JComponentHelper::renderComponent() /var/www/html/joomla/libraries/cms/application/administrator.php:98
5 JComponentHelper::executeComponent() /var/www/html/joomla/libraries/cms/component/helper.php:380
6 require_once() /var/www/html/joomla/libraries/cms/component/helper.php:405
7 JControllerLegacy->execute() /var/www/html/joomla/administrator/components/com_login/login.php:22
8 LoginController->login() /var/www/html/joomla/libraries/legacy/controller/legacy.php:728
9 JApplicationAdministrator->login() /var/www/html/joomla/administrator/components/com_login/controller.php:58
10 JApplicationCms->login() /var/www/html/joomla/libraries/cms/application/administrator.php:327
11 JApplicationBase->triggerEvent() /var/www/html/joomla/libraries/cms/application/cms.php:858
12 JEventDispatcher->trigger() /var/www/html/joomla/libraries/joomla/application/base.php:106
13 JEvent->update() /var/www/html/joomla/libraries/joomla/event/dispatcher.php:160
14 call_user_func_array() /var/www/html/joomla/libraries/joomla/event/event.php:69
15 plgUserUserlogintracking->onUserLogin()
16 plgUserUserlogintracking->storeInDatabase() /var/www/html/joomla/plugins/user/userlogintracking/userlogintracking.php:133
17 plgUserUserlogintracking->sendMail() /var/www/html/joomla/plugins/user/userlogintracking/userlogintracking.php:87
18 JMail->addRecipient() /var/www/html/joomla/plugins/user/userlogintracking/userlogintracking.php:52
19 JMail->add() /var/www/html/joomla/libraries/joomla/mail/mail.php:303
20 call_user_func() /var/www/html/joomla/libraries/joomla/mail/mail.php:285
21 PHPMailer->addAddress()
22 PHPMailer->addOrEnqueueAnAddress() /var/www/html/joomla/libraries/vendor/phpmailer/phpmailer/class.phpmailer.php:797
Since I cannot get past this error, how to I update HikaShop with the most current version?
Help - Website is unusable.