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Hi, I'm sorry if this isn't an appropriate place for this question.
I am trying to add an xUnit test project to my solution (framework .Net 5.0). Once I add the project as described in numerous tutorials I am getting the following error resulting in the following message "the type or namespace name "Fact", "FactAttribute" could not be found, are you missing a using statement. "
Here is the error:
Error occurred while restoring NuGet packages: An error occurred while retrieving package metadata for 'Microsoft.CSharp.4.0.1' from source 'C:\Program Files\dotnet\sdk\NuGetFallbackFolder'.
If I do a dotnet restore in the CLI I get the following:
C:\Program Files\dotnet\sdk\5.0.403\NuGet.targets(131,5): error : An error occurred while retrieving package metadata for 'Microsoft.CSharp.4.0.1' from source 'C:\Program Files\dotnet\sdk\NuGetFallbackFolder'. [C:\Users\ia\source\repos\AlgoExpert3\AlgoExpert3.sln]
C:\Program Files\dotnet\sdk\5.0.403\NuGet.targets(131,5): error : '.', hexadecimal value 0x00, is an invalid character. Line 1, position 1. [C:\Users\ia\source\repos\AlgoExpert3\AlgoExpert3.sln]
Note: When the project gets added a using statement is also created: using Xunit
Here is the .csproj:
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<TargetFramework>net5.0</TargetFramework>
<IsPackable>false</IsPackable>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
<PackageReference Include="xunit" Version="2.4.1" />
<PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
<PrivateAssets>all</PrivateAssets>
</PackageReference>
<PackageReference Include="coverlet.collector" Version="3.0.2">
<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
<PrivateAssets>all</PrivateAssets>
</PackageReference>
</ItemGroup>
</Project>
The project is completely empty, I haven't written any code anywhere. This is just step 1. Any help would be greatly appreciated!
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
Hi @Alina Nakhamchik ,
Error occurred while restoring NuGet packages: An error occurred while retrieving package metadata for 'Microsoft.CSharp.4.0.1' from source 'C:\Program Files\dotnet\sdk\NuGetFallbackFolder'.
From the error message, it relates the Microsoft.CSharp.4.0.1, have you installed this package in your main project and the XUnit test project? If you install it, try to remove it.
If you are not using the Micrsoft.CShartp.4.0.1 package, try to clear the Nuget local cache: Starting in Visual Studio 2022, use the Tools > NuGet Package Manager > Package Manager Settings menu command, then select Clear All NuGet Cache(s).
Besides, with referring the Unit testing C# in .NET Core using dotnet test and xUnit, I also create a sample, everything works well on my side, you can check the official document and the sample code.
Best regards,
Dillion
Hi Dillion! Thank you for responding -- I am not using the Microsoft.Csharp.4.01, and I'd tried to clear the cache before :( I tried it again and restarted visual studio, same result. It's clearly stuck somewhere... I don't think it's clearing the NuGet cache.