ASP.NET Core - HTTP Error 502.5 Process Failure

It seems whenever I work on an ASP.NET Core website, I always seem to get the most unhelpful error when deploying to production:

HTTP Error 502.5 - Process Failure

I have no problem running the ASP.NET Core site whilst developing from within a local environment.

From past experience, the HTTP 502.5 error generally happens for the following reasons:

1. The ASP.NET Core framework is not installed or your site is running the incorrect version.
2. Website project incorrectly published.
3. Potential configuration issue at code level.

Generally when you successfully publish a deployable version of your site, you'd expect it to just work. To get around the deployment woes, the solution is to modify your .csproj file by adding the following setting:

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

Once this setting has been added, you'll notice when your site is re-published a whole bunch of new DLL files are now present, forming part of all the dependencies a site requires. It's strange a normal publish does not do this already and what's even stranger is I have a different .NET Core site running without having to take this approach.

For any new .NET Core sites I work on, I will be using approach going forward.

Useful Links

• Force ‘dotnet publish’ to publish dependencies using PublishWithAspNetCoreTargetManifest
• ASP.NET Core 2.0 on IIS error 502.5