Nate McMaster

None of the code in this project adds this header. Have you checked if there is something happening automatically in the ASP.NET Core framework itself? I did a quick search...

If I remember right, I think @huesie ran into this issue as well, and solved it by forking this project and adding automatic fetching of the staging server CA certs....

I've just merged https://github.com/natemcmaster/LettuceEncrypt/pull/279. Can you take a look at this and see if it solves your problem?

You can also test with https://www.nuget.org/packages/LettuceEncrypt/1.3.0-beta.246

@netclectic can you share the steps you are using so I can reproduce the problem?

Have you tried using the `AdditionalIssuers` option? https://github.com/natemcmaster/LettuceEncrypt/blob/4dfcf037ba0ebde9109c7ba503be39c094bc5e0d/src/LettuceEncrypt/LettuceEncryptOptions.cs#L51-L65

I would prefer to avoid breaking changes if we can. Does this approach work instead? https://github.com/natemcmaster/LettuceEncrypt/pull/290

I've released https://github.com/natemcmaster/LettuceEncrypt/pull/290 to nuget as version 1.3.1. Please let me know if that works for you.

Did you implement DNS validation? https://github.com/natemcmaster/LettuceEncrypt#when-using-dns-01

The DNS challenge support was implemented by another contributor, so I didn't test myself, but I found this example on GitHub https://github.com/IronWatch/IronNAC/blob/543b4ec803467e92921c1608d1c772b48052933e/src/CaptivePortal/Daemons/WebDaemon.cs#L87-L91