HTTP with NTLM authentication

Hey guys, I’ve been struggling the last couple of days with this subject. My company works with a .NET web api with NTLM authentication and I need to make the ionic app I’ve developed comunicate with this web api.

I’ve tested GET/POST with Postman and it works perfectly, I get authenticated with no problem but when I try to http from the ionic app the response is always 401 - Unauthorized.

Has anyone been through this problem?

Thanks in advance

EDIT: after several days without success my company decided to migrate the app to Xamarin. Anyway if you find a stable solution for this you’re welcome to share. Thanks.

Same problem here.

In my case we have a rest api exported from navision and I have to connect an Ionic app.

In my case with postman and autenticarion Ntlm with user, password and domain configured the response is always 401

Can someone give any help


I don’t even know what NTLM is, but you might want to read some CORS documentation. The key point is that there is a “safelist” of headers that are deemed immune to CORS concerns, and if you are relying on headers outside that list, you need to care about CORS.

Did you solved your problems? I would like to build an app that connects to an IIS with NTLM Authentification.

This is no CORS problem.

I’m sorry to say but at the time I did not manage to find a solution for this.

You’re using NTLM and device dont use NTLM but remember the phone have a wireles connection,
you have this problem for that

you would have to try to establish a type of permission in the authentication to specify http as well or another type of authentication…

Tell me a little, in Xamarin are you using HTTP too?
because if so, can you try to share the code of your http request service compared to that of postman?