Publish error: Found multiple publish output files with the same relative path

Question

When I publish my ABP project I get the following error:

C:\Program Files\dotnet\sdk\6.0.100-rc.1.21458.32\Sdks\Microsoft.NET.Sdk
\targets\Microsoft.NET.ConflictResolution.targets(112,5): 
error NETSDK1152: Found multiple publish output files with the same relative path: 

D:\Github\volo\abp\lepton-theme\src\Volo.Abp.AspNetCore.Mvc.UI.Theme.Lepton\compilerconfig.json,
D:\Github\volo\abp\bookstore\src\Acme.BookStore.Theme\compilerconfig.json, 

D:\Github\volo\abp\lepton-theme\src\Volo.Abp.AspNetCore.Mvc.UI.Theme.Lepton\package.json, 
D:\Github\volo\abp\bookstore\src\Acme.BookStore.Web\package.json. 

D:\Github\volo\abp\bookstore\src\Acme.BookStore.Web\Acme.BookStore.Web.csproj

Answer 1

Issue:

The issue raises after .NET 6 migration. There's a new feature that blocks multiple files from being copied to the same target directory with the same file name. See https://learn.microsoft.com/en-us/dotnet/core/compatibility/sdk/6.0/duplicate-files-in-output

Solution #1 (workaround):

You can add the following build property to all your publishable (*.Web) projects' *.csproj files. This property will bypass this check and works as previously, in .NET5.

<PropertyGroup>
 <ErrorOnDuplicatePublishOutputFiles>false</ErrorOnDuplicatePublishOutputFiles>
</PropertyGroup>

Solution #2:

Exclude the problematic files to be copied to the output folder. In this example we'll exclude these files: compilerconfig.json and package.json.

Add the following lines to your common.props (located in the root directory of your solution):

<Content Remove="compilerconfig.json;package.json"/>
<None Include="compilerconfig.json;package.json">
  <ExcludeFromSingleFile>true</ExcludeFromSingleFile>
  <CopyToPublishDirectory>Never</CopyToPublishDirectory>
</None>