question

michael-smith15894 avatar image
michael-smith15894 asked ·

Unauthorized for this grant type - OAU-250

Hello Team,


We want to implement calling functionality in our Application for that we have decided to use RingCentral for that first we need to check it in the demo application. We are using PHP Package.


Here are the details of our Demo Application.


Application Name: SAMI-Aid

Client ID: gyNTMqexxxxxxx
Client Secret:
vU35UBKyxxxxx

Phone number: 1608729xxxx

Username:michaelsmith@samiaid.com

Application Type: Private

Platform Type: Server/Web

Permissions Needed : CallControl , RingOut, SMS, VoIP calling, ReadCallLog, SubscriptionWebhook


Now when I am trying to generate an access token using curl request I got an error like below


curl Request :


curl -X POST "https://developers.ringcentral.com" panel, It's working fine. Please find Attachment

General Topic
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anton-nikitin avatar image
anton-nikitin answered ·
For security reasons you have to use 3-legged OAuth flow with authorization_code grant type in web applications. See  https://developers.ringcentral.com/guide/basics/oauth#authorization-code-flow
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Phong Vu avatar image
Phong Vu answered ·
If you move on with the current app, see this quick start for a demo  https://developers.ringcentral.com/guide/authentication/quick-start/authorization-flow/php

Otherwise, if you want to use the password flow authentication, create a new app and select the Server-only (No UI) for the Platform Type. See this demo  https://developers.ringcentral.com/guide/voice/quick-start/php
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Anirban avatar image
Anirban answered ·

If you're using an OAuth 2.0 request using the OAuth 2.0 password grant (grant_type=password), then your application you created should in the RingCentral Developer Portal should be Password flow .

Please note, application created with different platform type will have different grant_type.

For example, application created for platform type = browser based will have grant_type=Authorization Code | Implicit | Refresh Access Token where as application for platform type = Desktop/Windows will have grant_type= Authorization Code | Password flow |Refresh Access Token

So in order to use (grant_type=password) you need to have application created with platform type that support Password flow

Here is wonderful way it has answered with animated Gif image that will easily help you to understand the proccess: https://stackoverflow.com/questions/47692828/ringcentral-auth-token-failed-in-curl-call-unauthorized-for-this-grant-type/47745436#47745436

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