If you are really still using osTicket 1.9.4, then you cannot use PHP 7.0 which I believe wasn't support until version 1.10If you have to use PHP 7.0, I have seen it suggested that you upgrade to 1.9.15 first, then to 1.10There have been several problems reported with PHP 7.0 that have been resolved by backing down to PHP 5.6