title: Project '..\..\Common\Common.csproj' targets 'net5.0'. It cannot be referenced by a project that targets '.NETStandard,Version=v2.0'
body: <p>I am creating an application using Xamarin.Forms, and in my solution I have three projects that are conflicting with Target Framework types when I run the build.</p>
  <p><img src="https://i.stack.imgur.com/CIZU2.png" alt="Solution Explorer" /></p>
  <p>As shown in the image above, CommonTest is my Testing project, Common is what I am using as a library to store classes used, and SimTools is what I am working out of to create the app.</p>
  <p><a href="https://i.stack.imgur.com/NPxkw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/NPxkw.png" alt="Visual Studio Error List" /><br />
  <br><sup>click to enlarge</sup></a></p>
  <p>Currently, when I try to add a reference in SimTools to the Common project to use the classes, I get the error: <code>&quot;Project '..\..\Common\Common.csproj' targets 'net5.0'. It cannot be referenced by a project that targets '.NETStandard,Version=v2.0'.&quot;</code></p>
  <p>The SimTools project target framework is .NET Standard 2.0, and the Common and CommonTest projects' target framework is .NET 5.0.</p>
  <p>I've tried many combinations of changing the target framework for the Common Projects (changing to .NET Core versions), and the SimTools project (.NET Standard versions).</p>
  <p>Additionally, I've referred to Microsoft's documentation regarding what frameworks support one another, and these combinations still show errors when I try to build.</p>
  <p><a href="https://docs.microsoft.com/en-us/dotnet/standard/net-standard" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/dotnet/standard/net-standard</a></p>
  <p>What is the minimum target framework version I need to set for SimTools and Common to allow SimTools to have a reference to Common?</p>