Please note that a copy of the Target.Abacus.Jobs.Service.exe.config file (located in the Abacus Jobs Service folder) and Web.config file (located in the root directory of the Abacus Admin, Provider Portal and Job service installations) should be taken before upgrading, as the upgrade process will replace these.
You'll need to update the Abacus database for each major build, so you'll upgrade first to 23.1, then 24.1, and finally to 25.1.
However, you only need to run version 25.1 of the Access Suite Installer to install Abacus Admin, Provider Portal, and Job Service.
You also only need to copy over the version 25.1 upgrade files for Abacus A4W, replacing the current version.
Note: Make sure to take a copy of the Target.Abacus.Jobs.Service.exe.config file (found in the Abacus Job Service folder) and the Web.config file (located in the root directory of the Abacus Admin, Provider Portal, and Job Service installations) before upgrading.