The "ResolvePackageAssets" task failed unexpectedly - System.TypeLoadException

Question

I am trying to set up visual studio 2019 on macos (10.14.3), but when attempting to build a default web MVC project I get this dependency error:

    Target _CheckForNETCoreSdkIsPreview:
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.RuntimeIdentifierInference.targets(151,5): message NETSDK1057: You are using a preview version of .NET Core. See: https://aka.ms/dotnet-core-preview
Target ResolvePackageAssets:
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018: The "ResolvePackageAssets" task failed unexpectedly.
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018: System.TypeLoadException: Could not resolve type with token 0100003f from typeref (expected class 'NuGet.Packaging.Core.PackageDependency' in assembly 'NuGet.Packaging, Version=5.0.0.4, Culture=neutral, PublicKeyToken=31bf3856ad364e35')
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets+CacheWriter.GetPlatformPackageExclusions () [0x000d7] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets+CacheWriter..ctor (Microsoft.NET.Build.Tasks.ResolvePackageAssets task, System.IO.Stream stream) [0x0009b] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets+CacheReader.CreateReaderFromDisk (Microsoft.NET.Build.Tasks.ResolvePackageAssets task, System.Byte[] settingsHash) [0x0003a] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets+CacheReader..ctor (Microsoft.NET.Build.Tasks.ResolvePackageAssets task) [0x00015] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets.ReadItemGroups () [0x00000] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.ResolvePackageAssets.ExecuteCore () [0x00018] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.NET.Build.Tasks.TaskBase.Execute () [0x00000] in <9524e6fbf1724027a475d15b01fab866>:0 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute () [0x00023] in /Users/builder/jenkins/workspace/build-package-osx-mono/2018-10/external/bockbuild/builds/msbuild-15/src/Build/BackEnd/TaskExecutionHost/TaskExecutionHost.cs:573 
    /usr/local/share/dotnet/sdk/3.0.100-preview3-010431/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(228,5): error MSB4018:   at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask (Microsoft.Build.BackEnd.ITaskExecutionHost taskExecutionHost, Microsoft.Build.BackEnd.Logging.TaskLoggingContext taskLoggingContext, Microsoft.Build.BackEnd.TaskHost taskHost, Microsoft.Build.BackEnd.ItemBucket bucket, Microsoft.Build.BackEnd.TaskExecutionMode howToExecuteTask) [0x00212] in /Users/builder/jenkins/workspace/build-package-osx-mono/2018-10/external/bockbuild/builds/msbuild-15/src/Build/BackEnd/Components/RequestBuilder/TaskBuilder.cs:784 
Done building target "ResolvePackageAssets" in project "TestingApp.csproj" -- FAILED.

Done building project "TestingApp.csproj" -- FAILED.

Build FAILED.

I also tried to run it from terminal with dotnet run and it works, but I cannot use Visual Studio. Thanks.

Solution 1

Just remove BIN and OBJ directories from the project and rebuild.

Solution 2

Try from command line:

• dotnet clean
• dotnet build

It worked for me. Take a look here for more info

Solution 3

Root cause :-

This error due to Nuget packages version compatibility different in projects(Shared project,iOS Project,Android Projects).

Solution:-

1.Update the each Nuget packages where shows update version in front of nuget package.

2.Clean solution.

3.Build Solution,

Solution 4

In my case. Go to C:\Program Files(x86)\Microsoft Visual Studio\Shared then create a new folder name is "NugetPackages"

Build and run the program again, Problem is fixed.

View more solutions

Comments

[bryoncline]

I was getting this error until I created an empty folder on: c:\microsoft\xamarin\nuget

[Isidore Ducasse]

thanks for the answer. it didn't work unfortunately. the error persists in VS and I cannot build the project using VS.

[Missy]

I did this and got a lot of errors but did it several times then built the project from VS and it worked. I used the VS command line.

[Sipke Schoorstra]

I think this worked for me, in that it made me realize that I had an instance of the app running, so stopped that one (and deleted the binaries all the same). So I'm not sure if that was in fact the issue, but it helped all the same.

[Łukasz Sypniewski]

In my case error was occurring when building Docker image. Adding the following to .dockerignore helped: **/bin **/obj bin/ obj/