I would suggest (if you are using Linux) to crank up error_reporting = E_ALL in php.ini and see if anything comes up in the logs (don't forget to restart your webserv), although, I am not convinced you will find anything useful, as failure would come up as error most likely, but I have seen some sysadmins disabling almost all output, except fatal errors. Again, what ntozier said - check mail logs :) When a guest creates a ticket, does it show up in maillog as outgoing? Or it doesn't even get to that? If it doesn't get to that, then:1) Check your template for sending e-mail when new ticket is created, make sure it does not have any warning, e.g., about variables which do not work. Make sure you have default/update language package installed (for the sake of completeness).2) If there is function issue, it should show up in error_log of httpd.If it does show up in maillog, then it get gets blocked by something, that is not osticket.