Please refer the below article for reference
Please note the below points while configuring Oauth
1. Oauth is released in Version 11 only.
2. If you are using Linux server, the EWS feature will be available only after Version 11 builds.
3. Kindly use firefox browser to configure.
4. Ensure the redirect URL is the same as the URL configured in the Admin >> Self Service Poral >> Configure alias URL accessible to the internet. Use the same URL to access the application while configuring Oauth, not localhost or public IP.
5. Use the below for Scope field.
Scope: EWS.AccessAsUser.All, offline_access .
6. Enable browser pop-up so that the MS authentication pop-up appears.
Using a Firefox browser, follow the steps mentioned in the below link to configure EWS Oauth in Support Center Plus.
https://www.youtube.com/watch?v=cwTpeIrflkQ
Please find the below general settings for Oauth EWS configuration below.
Connect URL: https://outlook.office365.com/EWS/Exchange.asmx >> Just copy and paste this on your end.
Client ID: You can follow the steps in above Oauth configuration.
Client Secret: You can follow the steps in above Oauth configuration.
Authentication URL: You can follow the steps in above Oauth configuration.
Token URL: You can follow the steps in above Oauth configuration.
Scope: EWS.AccessAsUser.All, offline_access >> Use the scope value as aforementioned, just copy and paste it into the scope field.