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Microsoft Dynamics NAV (Archived)

Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

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Posted on by 10

Dear experts,

I'm testing the API NAV 2018 cu 2 to integrate with demo e-commerce website. my problem is i cannot connect to the api from using ip or computer name. with chrome everything is fine, however when i tried using POSTMAN it shows error 401. 

6170.22222.png

>>>> this image shows available api when i access via chrome

6170.22222.png

>>>> this is the error when i tried using POSTMAN. i tried to change the authentication type to basic, but not working.

I also have followed the steps in another blogpost by saurav. but the image shown in that post all shows using localhost instead of ip or computer name.

anyone can help???

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  • sanpatHemlock Profile Picture
    5 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    NTLM authentication works perfect! Thnx.

  • Community Member Profile Picture
    on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    Hi,

    Do you have NST authentication as "Windows"? Try to set it as "NavUserPassword"

  • Suggested answer
    Community Member Profile Picture
    on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    Had the same issue, Error 401 when using Postman, but everything worked fine from Chrome. 

    I used NTLM authentication to resolve it. 

    Set Service Tier to "Use NTLM Authentication" (General Section)

    Use Postman (windows application not Chrome extension) and in the Authorization tab select "NTLM Authentication". Enter correct credentials of user in the DB. 

    Hope this helps

    Dave

  • Suggested answer
    Saurav.Dhyani Profile Picture
    14,314 Super User 2025 Season 1 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    Hope this helps!

    saurav-nav.blogspot.in/.../microsoft-dynamics-nav-2018-api-part-3.html

  • Suggested answer
    Andrey Baludin Profile Picture
    3,941 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    I've run it with Postman only after changing authorization to NTLM on NAV Instance and at Postman. So try this way.

    My experience is here:

    community.dynamics.com/.../how-to-obtain-data-from-nav-standard-apis

  • stevenleo Profile Picture
    10 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    still not working

    55555.png

    55555.png

    i wonder if i doing something wrong? 

    i tried to deploy another VM in azure, but i'm still facing the same problem.

  • Suggested answer
    Suresh Kulla Profile Picture
    47,789 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    For the password use the Web Service Access Key. 

    docs.microsoft.com/.../devenv-develop-connect-apps-for-fin

  • stevenleo Profile Picture
    10 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    @stefano, yes it is identical.

    @suresh, already tried using basicauth, with my administrator user & password. but it is not working.

    42320.4444.png

    42320.4444.png

  • Suggested answer
    Suresh Kulla Profile Picture
    47,789 on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    Check the Headers and specify the Authorization properly. check this link

    www.getpostman.com/.../authorization

  • Suggested answer
    Stefano Demiliani Profile Picture
    37,166 Most Valuable Professional on at
    RE: Error 401 Unauthorized in POSTMAN - Testing NAV 2018 API

    Is the request Header the same in all two cases (Chrome and Postman)?

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