Web Application build error with net6.0 framework, Failed to sign apphost with error code 0

[techwitz]

Web Application build error with net6.0 framework.

I am working on MAC and dotnet core 3.1, 5.0 and 6.0 versions are installed on my machine. I not able to build Web Application on my machine due to shared error in this ticket.

I can build web application in target framework net5.0 but not with net6.0 and console, class library projects' build successfully. I tried to build using command line, VS 2022/2019 but no success.

Project file code as below and this is empty Web API project.

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.1.5" />
  </ItemGroup>

</Project>

To Reproduce

Exceptions (if any)

/usr/local/share/dotnet/sdk/6.0.100-rc.2.21505.57/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(5,5): Error NETSDK1177: Failed to sign apphost with error code 0: /Users/ajandersingh/Projects/WebAppTest/WebAppTest/obj/Debug/net6.0/apphost: is already signed
(NETSDK1177) (WebAppTest)

Further technical details

• Include the output of dotnet --info
• VS 2022 Preview and VS 2019

Please assist to resolve code build error. I apologies if I have posted issue is not relevant to reported category

[dsplaisted]

@vitek-karas @mateoatr @agocke for triage

[agocke]

It looks like up-to-date checking might be confused. If you clear the obj directory and rebuild, does the error still appear?

[aflores]

I had a similar issue on a Mac using dotnet 6, which is a console application described in:
https://docs.microsoft.com/en-us/learn/modules/work-with-cosmos-db/3-exercise-work-cosmos-db-dotnet

After looking around, the fix for me was to editing the project file and adding:

... true ...

[khellinx]

I'm having the same issue, without significant changes to our project files. (mac, dotnet6)
Removing the obj folder and rebuilding does not solve it.
I will report back when I've found a solution.

[khellinx]

Uninstalling the dotnet SDK and reinstalling worked for me. (v6.0.101)
To uninstall, I followed the following docs:
https://docs.microsoft.com/en-us/dotnet/core/install/remove-runtime-sdk-versions?pivots=os-macos

Don't know what might have caused this to happen but I've tried (a combination of) the following:

• dotnet clean
• manually removing obj folders
• removing all nuget packages
• remove + reset git dir
• ...
  None of which worked until reinstalling the SDK.

This happened after my battery died when multiple asp net apps were running.

[shockliang]

sudo xcode-select -r fixing the issue for me....

[joejo-unity]

I have tried all these solutions (UseAppHost true, clean all folders, reset xcode-select) to no avail. Anything else I can try here???