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OpenAPI issue

Jonathan 20 Reputation points
2026-02-03T14:23:41.73+00:00

Hi,

Can you help it below? How to fix it? Originally I was with this error "The type or namespace name 'OpenApi' does not exist in the namespace 'Microsoft.AspNetCore' (are you missing an assembly reference?)"

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Developer technologies | C#
Developer technologies | C#
An object-oriented and type-safe programming language that has its roots in the C family of languages and includes support for component-oriented programming.
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  1. Bruce (SqlWork.com) 82,596 Reputation points Volunteer Moderator
    2026-02-03T22:37:52.1133333+00:00

    show your project file. should look like:

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

  <PropertyGroup>
    <TargetFramework>net10.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.2" />
  </ItemGroup>

</Project>

    also try (after checking project file):

    % dotnet restore
% dotnet build
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  2. Jonathan 20 Reputation points
    2026-02-04T01:17:01.41+00:00

    Here is the project details

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