the Microsoft Graph API will soon be required for new Microsoft Exchange Online
IMAP. Because [Microsoft is deprecating IMAP usage with Basic Authentication](https://techcommunity.microsoft.com/t5/exchange-team-blog/announcing-oauth-2-0-support-for-imap-and-smtp-auth-protocols-in/ba-p/1330432), the Microsoft Graph API will soon be required for new Microsoft Exchange Online
mailboxes.
To configure GitLab for Microsoft Graph, create an application in the
Azure Active Directory:
1. Sign in to the [Azure portal](https://portal.azure.com).
1. Search for and select `Azure Active Directory`.
1. Under `Manage`, select `App registrations` > `New registration`.
1. Enter a `Name` for your application, such as `GitLab Mail`. Users of your app might see this name, and you can change it later.
1. If `Supported account types` is listed, select the appropriate option.
1. Leave `Redirect URI` blank. This is not needed.
1. Select `Register`.
1. Under `Manage`, select `Certificates & secrets`.
1. Under `Client secrets`, select `New client secret`, and enter a name.
1. Under `Expires`, select `Never`, unless you plan on updating the credentials every time it expires.
1. Select `Add`. Record the secret value in a safe location for use in a later step.
1. Under `Manage`, select `API Permissions` > `Add a permission`. Select `Microsoft Graph`.
1. Select `Application permissions`.
1. Under the `Mail` node, select `Mail.ReadWrite`, and then select Add permissions.
1. If `User.Read` is listed in the permission list, you can delete this.
1. Click `Grant admin consent` for these permissions.
See the [Microsoft instructions](https://docs.microsoft.com/en-us/azure/active-directory/develop/quickstart-register-app)
To configure GitLab for Microsoft Graph, you will need to register an
OAuth2 application in your Azure Active Directory that has the
`Mail.ReadWrite` permission for all mailboxes. See the [MailRoom step-by-step guide](https://github.com/tpitale/mail_room/#microsoft-graph-configuration)
and [Microsoft instructions](https://docs.microsoft.com/en-us/azure/active-directory/develop/quickstart-register-app)
for more details.
You will need the following configuration items:
- Tenant ID for your Azure Active Directory
- Client ID for your OAuth2 application
- Client secret your OAuth2 application
##### Restrict mailbox access
For MailRoom to work as a service account, the application you create
