On building the project I am getting this error.
Error NETSDK1004 Assets file'J:\Test\core\fx-core\obj\project.assets.json' not found. Run a NuGetpackage restore to generate this file. FxCore C:\ProgramFiles\dotnet\sdk\3.1.201\Sdks\Microsoft.NET.Sdk\targets\Microsoft.PackageDependencyResolution.targets 234
So to solve this I am running the command dotnet restore in package manager console. But on running I'm getting the below error.
PM> dotnet restore J:\Test\core\fx-core\FxCore.csproj(3,3): warningMSB4011: "C:\ProgramFiles\dotnet\sdk\3.1.201\Current\Microsoft.Common.props" cannot beimported again. It was already imported at "C:\ProgramFiles\dotnet\sdk\3.1.201\Sdks\Microsoft.NET.Sdk\Sdk\Sdk.props (40,3)".This is most likely a build authoring error. This subsequent importwill be ignored. C:\ProgramFiles\dotnet\sdk\3.1.201\Sdks\Microsoft.NET.Sdk\Sdk\Sdk.targets(37,3):warning MSB4011: "C:\ProgramFiles\dotnet\sdk\3.1.201\Microsoft.CSharp.targets" cannot be importedagain. It was already imported at "J:\Test\core\fx-core\FxCore.csproj(118,3)". This is most likely a build authoring error. This subsequentimport will be ignored. C:\ProgramFiles\dotnet\sdk\3.1.201\NuGet.targets(124,5): error : Value cannot benull. (Parameter 'folderName') [J:\Test\core\fx-core\FxCore.sln] PM>
How to solve this issue?
.Net Target framework: 4.6.1
Visual Studio: 2019 (16.5.2)
Project Type : Class library
Update:
Adding csproj file based on @Lennart request
<?xml version="1.0" encoding="utf-8"?><Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" Sdk="Microsoft.NET.Sdk"><Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" /><PropertyGroup><Configuration Condition=" '$(Configuration)' == ''">Debug</Configuration><Platform Condition=" '$(Platform)' == ''">AnyCPU</Platform><ProjectGuid>{459BF9F7-69C7-4BBD-B566-CEFB992F88D5}</ProjectGuid><OutputType>Library</OutputType><AppDesignerFolder>Properties</AppDesignerFolder><RootNamespace>FX.Core</RootNamespace><AssemblyName>FxCore</AssemblyName><TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion><FileAlignment>512</FileAlignment><TargetFrameworkProfile /><GeneratePackageOnBuild>true</GeneratePackageOnBuild><Version>1.0.2.9</Version><Company>INTL FCStone</Company><Authors>INTL FCStone</Authors><Description>FxCore Assembly</Description><Copyright>Copyright 2018</Copyright><PackageReleaseNotes>version 1.0.2</PackageReleaseNotes><TargetFrameworkIdentifier>.NETFramework</TargetFrameworkIdentifier></PropertyGroup><PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU'"><DebugSymbols>true</DebugSymbols><DebugType>full</DebugType><Optimize>false</Optimize><OutputPath>bin\Debug\</OutputPath><DefineConstants>TRACE;DEBUG</DefineConstants><ErrorReport>prompt</ErrorReport><WarningLevel>4</WarningLevel></PropertyGroup><PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU'"><DebugType>pdbonly</DebugType><Optimize>true</Optimize><OutputPath>bin\Release\</OutputPath><DefineConstants>TRACE</DefineConstants><ErrorReport>prompt</ErrorReport><WarningLevel>4</WarningLevel></PropertyGroup><ItemGroup><Compile Remove="packages\**" /><Compile Remove="_CreateNewNuGetPackage\**" /><EmbeddedResource Remove="packages\**" /><EmbeddedResource Remove="_CreateNewNuGetPackage\**" /><None Remove="packages\**" /><None Remove="_CreateNewNuGetPackage\**" /></ItemGroup><ItemGroup><Reference Include="Dapper, Version=1.50.2.0, Culture=neutral, processorArchitecture=MSIL"><HintPath>packages\Dapper.1.50.2\lib\net45\Dapper.dll</HintPath></Reference><Reference Include="EasyNetQ, Version=0.63.6.463, Culture=neutral, processorArchitecture=MSIL"><HintPath>packages\EasyNetQ.0.63.6.463\lib\net45\EasyNetQ.dll</HintPath></Reference><Reference Include="FXEntity, Version=1.0.1.12, Culture=neutral, processorArchitecture=MSIL"><HintPath>packages\FXEntity.1.0.2.12\lib\net45\FXEntity.dll</HintPath></Reference><Reference Include="log4net, Version=2.0.8.0, Culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a, processorArchitecture=MSIL"><HintPath>packages\log4net.2.0.8\lib\net45-full\log4net.dll</HintPath></Reference><Reference Include="Microsoft.Practices.ServiceLocation, Version=1.3.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL"><HintPath>packages\CommonServiceLocator.1.3\lib\portable-net4+sl5+netcore45+wpa81+wp8\Microsoft.Practices.ServiceLocation.dll</HintPath></Reference><Reference Include="Microsoft.Practices.Unity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=6d32ff45e0ccc69f, processorArchitecture=MSIL"><HintPath>packages\Unity.4.0.1\lib\net45\Microsoft.Practices.Unity.dll</HintPath></Reference><Reference Include="Microsoft.Practices.Unity.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=6d32ff45e0ccc69f, processorArchitecture=MSIL"><HintPath>packages\Unity.4.0.1\lib\net45\Microsoft.Practices.Unity.Configuration.dll</HintPath></Reference><Reference Include="Microsoft.Practices.Unity.RegistrationByConvention, Version=4.0.0.0, Culture=neutral, PublicKeyToken=6d32ff45e0ccc69f, processorArchitecture=MSIL"><HintPath>packages\Unity.4.0.1\lib\net45\Microsoft.Practices.Unity.RegistrationByConvention.dll</HintPath></Reference><Reference Include="Ninject, Version=3.2.0.0, Culture=neutral, PublicKeyToken=c7192dc5380945e7, processorArchitecture=MSIL"><HintPath>packages\Ninject.3.2.2.0\lib\net45-full\Ninject.dll</HintPath></Reference><Reference Include="RabbitMQ.Client, Version=3.6.6.0, Culture=neutral, PublicKeyToken=89e7d7c5feba84ce, processorArchitecture=MSIL"><HintPath>packages\RabbitMQ.Client.3.6.6\lib\net45\RabbitMQ.Client.dll</HintPath></Reference><Reference Include="System" /><Reference Include="System.configuration" /><Reference Include="System.Core" /><Reference Include="System.Web" /><Reference Include="System.Xml.Linq" /><Reference Include="Microsoft.CSharp" /><Reference Include="System.Data" /><Reference Include="System.Net.Http" /><Reference Include="System.Xml" /></ItemGroup><ItemGroup><Folder Include="Properties\" /><Compile Remove="Configuration\UspHostLoginValidateResult.cs" /><Compile Remove="Configuration\UspHostUserRoleMenuListResult.cs" /><Compile Remove="Properties\AssemblyInfo.cs" /><Folder Include="DataAccess\" /><Folder Include="DataAccess\Components" /><Folder Include="Diagnostics\" /><Folder Include="Diagnostics\Components" /><Folder Include="NetworkProtocols\" /><Folder Include="Unity\" /> </ItemGroup><ItemGroup><None Include="app.config"><SubType>Designer</SubType></None><None Include="packages.config" /></ItemGroup><ItemGroup><PackageReference Include="Connect.SSO" Version="3.5.6.1" /><PackageReference Include="Microsoft.AspNet.Mvc" Version="5.2.6" /><PackageReference Include="Dapper" Version="1.50.2.0" /><PackageReference Include="EasyNetQ" Version="0.63.6.463" /><PackageReference Include="log4net" Version="2.0.8.0" /><PackageReference Include="Microsoft.Practices.ServiceLocation" Version="1.3.0.0" /><PackageReference Include="Ninject" Version="3.2.0.0" /><PackageReference Include="RabbitMQ.Client" Version="3.6.6.0" /></ItemGroup><Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" /><!--<Target Name="PreBuild" BeforeTargets="PreBuildEvent"><Exec Command="


" /></Target>--></Project>