To update your DISE on-prem server you wan to follow the following steps.
First you want to download the latest version of the DISE Server (CX Portal) here: https://support.dise.com/support/solutions/articles/9000103333-on-prem-server
If you do not have access to the solution above please contact firstname.lastname@example.org and we will grant you access.
When you have the DISE Server .exe file on your server machine you want to run it to start the installer.
All settings from when you first installed the server will still be there, so if you do not want to change anything you can just hit next all the way through the installer.
Just make sure to check the paths along the way so they get installed in the same folder as the previous installation.
If there are things on the server you want to change while running the installer you can find the specifics on how to that here:
When the installation is done make sure that all the DISE services are running by going to the Taskmanager and the tab 'Services'.
All DISE Services are named 'DISE..'.