SQL Server is the Microsoft database server that runs underneath Best Practice, Medical Director and many other systems. The free version of SQL Server is sufficient until your medical database is large (10GB). At this time you must upgrade to the paid version or your system will stop working.

From time to time, the version of SQL Server (Free or Paid) will need to be upgraded at your clinic. Microsoft has ceased supporting older versions, and as the expiry date passes, clinics will need to upgrade to a newer SQL Server version.

To check your version of SQL Server
    

You can see from my test machine that it is running SQL Server version 15.0.4415.2 RTM Express Edition.

Everyone should be on a version starting with 13.x.xxxx.xxx or above.
Version 15 is called ‘SQL Server 2019’. The current latest version is 16.0.04175.1 and is from last month. Version 16 is ‘SQL Server 2022’
Mine says ‘Express Edition’ because I am using the free version of SQL Server.