How to debug oauth 2.0 access denied error

[zhuwbigdata]

Used both Curl and Postman to test and got "{"error_description":"access_denied","error":"server_error"}".  Tested with the user and the password,  and was able to log into dev instance w.o. any issue.

[dolanp_tapco]

This blog worked for me

1. https://community.servicenow.com/community?id=community_blog&sys_id=56086e4fdb9014146064eeb5ca961957