Hello,
For OnPrem I suggested to use:
community.dynamics.com/.../business-central-on-premise-oauth2-authentication_invalidcredentials
For SaaS, these settings may differ, here they are again, note that I am using a collection and environment variables.
1. Add New collection:
Type: OAUTH 2.0
Add auth data to: Request Headers
Access Tokens: Available Tokens
Header Prefix: Bearer
Token Name: S2S OAUTH2
Grant Type: Authorization Code
Callback Url: https : // api.businesscentral.dynamics.com/v2.0/Production/api/v2.0
Authorize URL: https : // login.microsoftonline.com/{{TENANTAADID}}/oauth2/v2.0/authorize
Access Token URL: https : // login.microsoftonline.com/{{TENANTAADID}}/oauth2/v2.0/token
Client ID: {{CLIENTID}}
Client Secret: {{CLIENTSECRET}}
Scope: {{SCOPE}} //NOTE THAT {SCOPE}} is a variable defined in postman: https : // api.businesscentral.dynamics.com/.default) (without the additional spaces to prevent reformatting of the url)
Client Authentication: Send client credentials in body
NOTE: add environmental values in Postman and add actual values for SCOPE, ClientID, etc.
You can clear cookies and then get new access token. The client ID must be added as an applicatdion to Azure AD in BC and consent must be granted first.
After that, add a new tab with GET and then the url for the admin center (and point it to the collection, use inherit from parent for authentication and save the tab first for changes to take effect).
Note that I also added some additional reply urls in the app registration for the api.businesscentral.dynamics.com, etc.
Hope it helps.