Could not load type

Question

First of all i thank you on your time and i hope that you can understand me even with English as broken as this one:

Could not load type 'Microsoft.EntityFrameworkCore.Infrastructure.IDbContextOptionsExtensionWithDebugInfo' from assembly 'Microsoft.EntityFrameworkCore, Version=3.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'

Tried to reinstall all packages, to manually put references, restarted PC,restarted VS2019 and even started new project but still error is there again.

I've been here but it didn't help.

services.AddDbContext<ApplicationDbContext>(options =>
                options.UseSqlServer(


Configuration.GetConnectionString("DefaultConnection")));

--.csproj

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

  <PropertyGroup>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <UserSecretsId>aspnet-ZavrsniRad01-F04B6A7E-6450-4254-8092-F42843F4615A</UserSecretsId>
  </PropertyGroup>


  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore" Version="3.0.0-preview6.19307.2" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="3.0.0-preview6.19307.2" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.UI" Version="3.0.0-preview6.19307.2" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.0.0-preview.18572.1" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="3.0.0-preview6.19304.10" />
    <PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="3.0.0-preview6.19304.6" />
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="3.0.0-preview6-19319-03" />
  </ItemGroup>

</Project>

Answer 1

Apparently i had to install EntityFrameworkCore.SqlServer preview6 to solve this error

Install-Package Microsoft.EntityFrameworkCore.SqlServer -Version 3.0.0-preview6.19304.10

Answer 2

I had the same problem with my test project and I saw that the Microsoft.EntityFrameworkCore.SqlServer was missing from my test packages, so I installed the latest version of it and my issue was resolved.

Note: If you are having the same issue with a test do make sure that the Microsoft.EntityFrameworkCore.InMemory version matches the Microsoft.EntityFrameworkCore.SqlServer just for consistency.