ActiveCollab has always prefixed tables with “acx_”, which is a different value than the user specified during installation. This is purely historical. Users were forced to install multiple applications within a single database. This meant that all applications had to “namespaceā€ their tables with a prefix. If application #1 had a user table, any other application could not have a table with the same name unless they added a prefix (app1_users or app2_users). Since version 5, ActiveCollab has retired the prefix for table prefixes in PHP apps you can self-host. VPS plans are now so affordable and common that you have complete control over your platform. You can create as many databases you wish. Even shared plans, which we don’t recommend, offer unlimited databases. It’s time for you to move on. You will need to prepare one empty database for the new ActiveCollab. This database can then be fully managed by the app. The upgrade script will move ActiveCollab 4 tables to a new database and remove the table prefix. The upgrade script will also ensure that your tables use a modern storage engine. We prefer to concentrate on the things that really matter (user experience, performance and features, etc.). Instead of dealing with limitations imposed by past hosting practices, we prefer to focus on what really matters (user experience, performance, features, etc.).