OAuth support for Microsoft GCCH accounts on Jira Cloud Incoming Mail

Issue Summary

Incoming Mail on Jira Cloud (JSW and JWM) supports connecting to Office 365 accounts using OAuth 2.0. However, it doesn't support GCC (Government Community Cloud) accounts. It isn't supported because regular Office 365 accounts connect to outlook.office365.com whilst GCC accounts connect to outlook.office365.us. Therefore, the connection is not established and the mail channel can't be connected using OAuth 2.0

Workaround

Since Microsoft will stop supporting Basic Authentication for GCCH customers by March 31, 2023, emails sent to your configured Microsoft mail server will not create new issues or add comments to existing issues. Currently, Jira Cloud does not support OAuth 2.0 for Microsoft GCC-High accounts. So, to keep receiving issues and comments via email, we recommend you turn on automatic forwarding in your Outlook account to the default email address in Jira Cloud by following the steps below:

1. On Microsoft Outlook, click the cog icon on the top right and select View all Outlook settings
   
2. Click Forwarding
   1. Select Enable forwarding and enter the default email address provided by Atlassian (as seen in the screenshot below)
      
      Navigate to cog icon > System > Incoming Mail or YourCloudURL.com/secure/admin/IncomingMailServers.jspa
   2. Optional: If you want a copy of the original message to remain in your mailbox, select Keep a copy of forwarded messages
3.  Select Save
4. On Jira, navigate to cog icon > System > Incoming Mail and select Add an incoming mail handler with the Default Cloud Mail Server you configured in step
5. Delete the incoming mail server that uses Basic Authentication

Once you have set up the automatic forwarding successfully, incoming mail will successfully create issues and comments in Jira Cloud.