Hi all,I'd seen a few reports of others with this problem, but none of the suggested fixes made any difference, so I've spent most of today buried in osTicket source code, debugging email piping on our live system. #partyAuto-responses were sending fine when tickets were created via the web (whether by staff or end-users), and new ticket notifications were being sent to staff, so I figured there had to be a pipe-specific bug somewhere.Sure enough, I eventually discovered that these headers were being added to emails by our Exchange 2010 server:X-Auto-Response-Suppress: DR, OOF, AutoReplyWhich was causing TicketFilter->isAutoReply() to return true, and suppressing the auto-response email.Commenting out this line in include/class.filter.php has sorted the problem for us:'X-Auto-Response-Suppress' => array('ALL', 'DR', 'RN', 'NRN', 'OOF', 'AutoReply'),Given the importance of auto-responses in enabling users to self-service their tickets, I'd suggest that this change might be required more widely. Alternatively, these lines in class.ticket.php could be removed / commented out to ensure that auto-responses are definitely sent at ticket creation time:if ($autorespond && $message->isAutoReply()) $autorespond = false;I hope this helps someone :)