ERROR - “Invalid_Client” or "Invalid_grant"

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Are you receiving an “Invalid_Client” or "Invalid_grant"?

 

The "Invalid_Client" error message is common for requests with wrong client ID or client secrets.

The "Invalid_grant" error message is common to have with one of the following scenarios.

1. The token has become invalid. This can happen when its lifecycle has expired or when you change the password (changing password invalidates tokens).

or

2. If you are trying to request a token when with some faulty parameters, eg. wrong client secret, wrong redirect URI, an old authorization code etc.