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imranesellko
New Member

Power BI report server REST API with postman NTLM Active Directory user unauthorize 401

Hi Gents,

I have a distributed setup

1- Server windows 2016- Power BI Report server is installed

2- Server windows 2016- SQL Server DB installed

Both are on same company domain and working fine. Now I have installed postman on my client machine ( same domain as both of my servers) and trying to get response from REST API. It gives unauthorize 401 response.

But when I use any browser, it works and I can see the JSON response

I created a local user on my windows server machine where Power BI report server is installed and postman able to authenticate local user with NTLM authentication but it gives 401 unauthorize error when I use my Domain Active directory user authentication.

 

So, the problem is: postman with NTLM authentication is giving 401 response for Active directory user, but ok for windows server local user.

Is there anything I am missing?

Thanks

2 REPLIES 2
d_gosbell
Super User
Super User

What format are you using for the domain user in Postman? Are you using just <username> or are you using <domain>\<username> ?

 

If prefixing the user with the domain name does not help you could try using the fiddler trick from this post windows authentication - Pass NTLM with Postman - Stack Overflow

@d_gosbell , thanks for the reply, Infact I am using postman for the testing purpose, later on I have to access API response from another application (named: zenoptics), so, even if i skip authentication with postman, it will not solve my problem because I am facing the same authentication issue with zenoptics application. I guess there is some issue with Domain user(active directory user) authentication while accessing REST API from any other application.

Is there any configuration or setting that we need to enable to access API response from another application with domain user autentication.

As I mentioned earlier, NTLM with postman works fine if I use local user credentials. It gives error only if I use active directory user ( I tested in both format ; username  and username with full domain name)

 

Thanks

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