title: Web Application build error with net6.0 framework, is already signed (NETSDK1177)
body: <p>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.</p>
  <p>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.</p>
  <p>Project file code as below and this is empty Web API project.</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;Project Sdk=&quot;Microsoft.NET.Sdk.Web&quot;&gt;
  
    &lt;PropertyGroup&gt;
      &lt;TargetFramework&gt;net6.0&lt;/TargetFramework&gt;
      &lt;Nullable&gt;enable&lt;/Nullable&gt;
      &lt;ImplicitUsings&gt;enable&lt;/ImplicitUsings&gt;
    &lt;/PropertyGroup&gt;
  
    &lt;ItemGroup&gt;
      &lt;PackageReference Include=&quot;Swashbuckle.AspNetCore&quot; Version=&quot;6.1.5&quot; /&gt;
    &lt;/ItemGroup&gt;
  
  &lt;/Project&gt;
  
  </code></pre>
  <h3>Exception</h3>
  <blockquote>
  <p>/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/abc/Projects/WebAppTest/WebAppTest/obj/Debug/net6.0/apphost: is
  already signed  (NETSDK1177) (WebAppTest)</p>
  </blockquote>
  <h3>Further technical details</h3>
  <pre><code>.NET SDK (reflecting any global.json):
   Version:   6.0.100-rc.2.21505.57
   Commit:    ab39070116
  
  Runtime Environment:
   OS Name:     Mac OS X
   OS Version:  11.6
   OS Platform: Darwin
   RID:         osx.11.0-x64
   Base Path:   /usr/local/share/dotnet/sdk/6.0.100-rc.2.21505.57/
  
  Host (useful for support):
    Version: 6.0.0-rc.2.21480.5
    Commit:  6b11d64e7e
  
  .NET SDKs installed:
    3.1.414 [/usr/local/share/dotnet/sdk]
    5.0.402 [/usr/local/share/dotnet/sdk]
    6.0.100-rc.2.21505.57 [/usr/local/share/dotnet/sdk]
  
  .NET runtimes installed:
    Microsoft.AspNetCore.App 3.1.20 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
    Microsoft.AspNetCore.App 5.0.11 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
    Microsoft.AspNetCore.App 6.0.0-rc.2.21480.10 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
    Microsoft.NETCore.App 3.1.20 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
    Microsoft.NETCore.App 5.0.11 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
    Microsoft.NETCore.App 6.0.0-rc.2.21480.5 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
  
  To install additional .NET runtimes or SDKs:
    https://aka.ms/dotnet-download
  </code></pre>