Upgrading SPS v3 to v4
When upgrading from SPS v3 to v4, you need to update your Windows Server and prerequisites first.
Installing .NET 9.0 runtimes
You need to install the latest .NET 9.0.x runtimes on the server where SPS is hosted.
To verify if you already have the required runtimes installed, run the following command in a terminal:
dotnet --list-runtimes
In the list, you need to see a line similar to the following:
Microsoft.AspNetCore.App 9.0.xx [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
It is safe to download and install the latest runtimes again, even if you already have them installed. The installer will detect the existing runtimes and will only install the missing ones, if any.
You can download the latest version of ASP.NET Core Runtimes 9 > Hosting Bundles from the official .NET website: https://dotnet.microsoft.com/en-us/download/dotnet/9.0.
Upgrading the app
After you have made the necessary changes to the appsettings.json file and you ensured your web server prerequisites are met, you can proceed with upgrading the app files.
To upgrade the app, follow the standard instructions Updating the SPS Plus application in this documentation.
This concludes the whole process of upgrading from SPS v3 to v4. You do not need to do any changes to the hosting server, IIS, or the database, except for the changes to the appsettings.json file described above.