dotnet watch on net6.0 project results in FileNotFoundException for SystemRuntime

[JoshWoodArup]

Description

When running the dotnet watch from .net 7 on a net6.0 project, a FileNotFoundException is thrown claiming that System.Runtime, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a could not be found. net7.0 and net5.0 projects work fine.

Reproduction Steps

dotnet new console -f net6.0
dotnet watch run

Expected behavior

The program should output Hello, World!.

Actual behavior

dotnet watch 🔥 Hot reload enabled. For a list of supported edits, see https://aka.ms/dotnet/hot-reload.
  💡 Press "Ctrl + R" to restart.
dotnet watch 🔧 Building...
  Determining projects to restore...
  All projects are up-to-date for restore.
  watchtest -> D:\Test\watchtest\bin\Debug\net6.0\watchtest.dll
dotnet watch 🚀 Started
Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.
File name: 'System.Runtime, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at System.Reflection.RuntimeAssembly.GetType(QCallAssembly assembly, String name, Boolean throwOnError, Boolean ignoreCase, ObjectHandleOnStack type, ObjectHandleOnStack keepAlive, ObjectHandleOnStack assemblyLoadContext)
   at System.Reflection.RuntimeAssembly.GetType(String name, Boolean throwOnError, Boolean ignoreCase)
   at System.Reflection.Assembly.GetType(String name, Boolean throwOnError)
   at System.StartupHookProvider.CallStartupHook(StartupHookNameOrPath startupHook)
   at System.StartupHookProvider.ProcessStartupHooks()
dotnet watch ❌ Exited with error code -532462766
dotnet watch ⏳ Waiting for a file to change before restarting dotnet...

Regression?

This is a regression from SDK 7.0.100-rc.2

Known Workarounds

This can be worked around by creating a global.json file and pointing it to the v6 SDK (thanks @nicholashead)

{
    "sdk": {
        "version": "6.0.403"
    }
}

Alternatively, adding any argument after dotnet watch run will work. e.g.

dotnet watch run bogus

(thanks @akorchev)

Configuration

.NET SDK:
Version: 7.0.100
Commit: e12b7af

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19044
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\7.0.100\

Host:
Version: 7.0.0
Architecture: x64
Commit: d099f075e4

Other information

It's possible that my installation is corrupted. However I have uninstalled and reinstalled several times

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[nicholashead]

I'm experiencing this as well. I worked around it for now by creating a global.json file and pointing it at the v6 SDK:

{
    "sdk": {
        "version": "6.0.403"
    }
}

[VictorMalcov]

I'm experiencing this as well. I worked around it for now by creating a global.json file and pointing it at the v6 SDK:

{
    "sdk": {
        "version": "6.0.403"
    }
}

This did not work for me.

[nicholashead]

@VictorMalcov it should work for the “dotnet” command line. Are you getting an error message or something else?

[axylophon]

I have the same issue. global.json fixes it temporarily

[akorchev]

I've hit this too and discovered this issue. Strangely enough putting anything after "run" seems to fix the problem (even without global.json) e.g. dotnet watch run bogus. Found it by dumb luck after a typo.

[VictorMalcov]

{
    "sdk": {
        "version": "6.0.403"
    }
}

I checked and my 6.0.401 folder was empty. I reinstalled .net 6 and everything works. Thanks!

[petunsecngmail]

Yesterday, After upload to VS 17.4.0, i have the same error. and I just reinstalled .net 6 and everything works.

[tanveerbadar]

Adding the global.json specified as a workaround above did not work for me, got this additional error instead:

error MSB4242: SDK Resolver Failure: "The SDK resolver "Microsoft.DotNet.MSBuildWorkloadSdkResolver" failed while attempting to resolve the SDK "Microsoft.NET.Sdk.Web". Exception: "Microsoft.NET.Sdk.WorkloadManifestReader.WorkloadManifestCompositionException: Workload manifest dependency 'Microsoft.NET.Workload.Emscripten' version '6.0.4' is lower than version '6.0.9' required by manifest 'microsoft.net.workload.mono.toolchain' [C:\Program Files\dotnet\sdk-manifests\6.0.300\microsoft.net.workload.mono.toolchain\WorkloadManifest.json]

I have no idea what is supposed to happen here.

However, the other workaround of dotnet watch run bogus did work perfectly.

P.S.: The file is still needed otherwise the project will target dotnet 7 SDK, since the update managed to uninstall dotnet 6 SDK. Again.

Would be interested to know if anyone got this recently after updating Visual Studio 2022/.NET Core 7.

[nicholashead]

Would be interested to know if anyone got this recently after updating Visual Studio 2022/.NET Core 7.

Yes, this is exactly when it started happening for me. I was not running any betas or anything.

[byroniac]

Would be interested to know if anyone got this recently after updating Visual Studio 2022/.NET Core 7.

Yes, this is exactly when it started happening for me. I was not running any betas or anything.

Same here.