Get Oauth access token return server_error access_denied

[Randy25]

I am trying to connect to the REST API to get incidents in my service now instance using OAuth code grant flow as described below:

OAuth authorization code grant flow

I can get a code from the first step, but when I try to request the access and refresh tokens I get a 401 unauthorized response with the body:

{"error_description":"access_denied","error":"server_error"}

I use OAuthClient library to post request and my URL is :

https://<instance>.service-now.com/oauth_token.do

My body/query params are:

grant_type=authorization_code&code=<code>&redirect_uri=<uri>&client_id=<id>&redirect=<redirecturl>

[Randy25]

I tried the suggestion, the result is access_denied too. Here are screenshots of Authorization Tab, Headers Tab, and Body Tab.

[ARG645]

Not sure why its not working. Its worth giving the below process a shot. They way to get the acess token seems very simple in the below link.

https://developer.servicenow.com/blog.do?p=/post/inbound-oauth-auth-code-grant-flow-part-1/

[Randy25]

I read the attached process before and it worked with postman "Get New Access Token" function, but I need to find out how to get access token with URL request. My application uses URL request.

It confused me for days. ;(

[Randy25]

Problem resolved. If I used postman to post request token URL directly, it will return access_denied. I used my application to redirect by web with the same request and got the access token successfully.

Thank you for the help 🙂