Hi I am facing an issue which when I log in using the Microsoft 365 SSO, it shows an error after I have logged into my Microsoft account which is same as the Administrator’s email. I have checked the redirected url and the api.
Was you Microsoft SSO working previously and stopped working, or is this your first time setting it up? SSO-related errors are logged in more detail in the system log, if you go into System Admin > View Log, see if you can find the error log and it may give you a specific error, such as authentication mismatch, it IP address refused, etc. This can help when troubleshooting the setup, as there are parts that need configured in both sides for everything to work smoothly (especially the redirect URI and IP address).
Based on the Invalid Client error, it sounds like there may be an issue with the Client ID or Client Secret. Be sure to check that there are no extra spaces or characters from copy-pasting these values. Also, here is an additional step to check, which looks like it could be a common cause of the invalid_client error: Microsoft OAuth2 - invalid client - osTicket Forum