.NET Core 3.1, as we always start with every article that talks about this version of .NET, was released for Windows, Linux, and macOS at December 3rd, 2019. It featured support for C# 8.0, F# 4.7, Windows Desktop application building, fast built-in JSON support, and more.
At July 12th of 2022, Microsoft have recently announced that .NET Core 3.1 will end its support at December 13th, 2022.
We’re nearing the abovementioned end of support date as more and more developers are migrating their .NET Core 3.1 applications to .NET 6.0 or higher. This is because Microsoft urged .NET Core 3.1 developers to migrate their applications to higher supported versions of .NET, such as the recently-released .NET 7.0 – which is known for its speed – or the latest LTS version, .NET 6.0.
After .NET Core 3.1 ends support, the “.NET Core” brand will be unsupported, too.
To upgrade your .NET application to latest supported version, open your project file and change the target runtime to, for example, net7.0. Make sure that you have installed the appropriate .NET SDK and updated your Visual Studio installation to the latest version. The Visual Studio installer will automatically take care of the SDK updates and deal with the unsupported components.
To get .NET 7.0, click on the below button.
Aptivi 
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