An assembly specified in the application dependencies manifest (…) was not found

Question

I upgraded Microsoft.AspNetCore from 2.0.3 to 2.0.5 and my WebAPI project, although running successfully locally, fails to start in production (IIS). Everything was fine in

Answer 1

In most case you get that error because there's misalignment of versions.

I changed the Microsoft.VisualStudio.Web.CodeGeneration.Design version, an it worked.

Before

<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="3.1.0" />

After

<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.2.4" />

Answer 2

To solve the first half of the error message, An assembly specified in the application dependencies manifest (…) was not found be sure to always use the publish output when deploying to a target sever.

For a self-contained application it can be found in

bin\Release\netcoreapp2.0\win81-x64\publish

or for framework-dependent deployments in

bin\Release\netcoreapp2.0\publish

The output in the directories above are meant to be used in development only, since they are specific to machine and user configuration built with.

Taken from a related answer.

Answer 3

Development machines usually have the SDK installed but on production the runtime only.

Add the following to your .csproj file and publish again.

<PropertyGroup>               
    <PublishWithAspNetCoreTargetManifest>false</PublishWithAspNetCoreTargetManifest>
</PropertyGroup>