I have installed the Identity server locally and set up oAuth on Creatio -screenshot attached-
I generate a token from the identity server like this 
Then use the token to authenticate OData like this 
and as you can see it is returning 401, I made sure the user has roles that make it able to read the data but still
Like
Orkhan,
Greetings, it is returning the Json data correctly
Greetings,
I tried to reproduce the issue on my side and everything works as expected:
- The integration was set up correctly.
- The technical user was created with all the required permissions (in case permissions were missing, the system would usually return 403 Forbidden rather than 401).
- The access token was generated correctly, which confirms that the client credentials are valid.
To narrow down the cause, please double-check the following:
- Make sure the token you paste into Postman does not contain any extra characters (such as spaces, quotes, etc.).
- Ensure that the token is still valid and not expired at the moment of the request.
Additionally, since you confirmed that the OData endpoint opens successfully in the browser and returns JSON, this means the service itself is available. In this case, a 401 Unauthorized in Postman usually indicates that the token provided there is not accepted by Creatio.
Could you please re-check the token details in Postman and try again? If the issue persists, kindly share the decoded token payload (without the signature) so we can verify the claims (use https://www.jwt.io/)