I am currently on 4.69.0 and cannot upgrade due to the latest MySQL requirements. Running: PHP Version 5.6.23 and 5.0.11. I am on a leased server where I have a lot of leeway on what can be done with PHP and MySQL. My hosting company which manages the server and also hosts their shopping cart application tell me the following: The latest Kayako requires an indexing feature that is only present in MySQL 5.7 or MariaDB 10.1. The very latest version of RedHat Enterprise Linux still uses the 5.5 version, so not even migrating to a newer server would resolve the issue. The only options available are: 1) Replace the running copy of MySQL on his server with a downloaded version of MariaDB 10.1 / MySQL 5.7 (doesn’t matter which). The problem here is that many other software dependencies on the server may break by doing this, so we’d have no way to know what would stop functioning correctly, either immediately or in the future. MariaDB does have a repository for doing this (https://mariadb.com/kb/en/mariadb/yum/), which should be supported for a while, so it is an option. The catch; if we do this, and it breaks the server, we’re going to charge for support time to fix it, now and in the future, and there are no guarantees it won’t seriously break something at some point, unexpectedly. 2) Create a (standalone) database server and do the same as the above. That eliminates the risk to other apps, Plesk, the OS, etc. as it’s only duties would be database. We can connect plesk to it so he can still manage databases on it, etc. You could also put other things on it like Miva Merchant stores, which would increase the performance by having the database duties moved to a second server. Having a dedicated database server would be $200/mo.