I was unable to script this, (using the link provided by user1977061), as the MSSQLService requires a restart afterwards to apply the change. Even after doing this it didn’t work, and instead I had to manually configure FILESTREAM usage via:
- SqlServer Configuration Manager
- Sql SQL Server Services
- SQL Server(MSSQLSERVER) [Properties]
- FILESTREAM tab – enable the first 2, and optionally 3rd check box.
Look at the SQLServer properties > Advanced > Running Values value for “Filestream Access Level” to ensure that the FILESTREAM is actually enabled if in doubt.