@[deleted]Right now, all I can think of is that spam rules or modified osticket files are causing this affect.Do you have checked spam filters or have you modified osticket?Do you have "Mailer Error"-entries in the "System Logs"-section of osticket?For example when the php mail function isn't able to send an email I see log entries there like this one:Mailer ErrorUnable to email via php mail function:"Tom Reagon" mail() returned failureLog Date: Mo., Sep 11 2017 12 nachm. IP Address: 192.168.178.20