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POP3/IMAP Connection and Optional Mail Forwarding

Included in	All Checkmk editions
Source Code License	Open Source
Supported Agents	Active

Logs in into an IMAP, POP3, EWS, or Microsoft Exchange Online mailbox to monitor whether or not the login is possible. An extended, optional, feature is, that the check can fetch all (or just some) mails from the mailbox and forward them as events to the Event Console.

The following protocols and authentication methods are supported:

IMAP and POP3: Username/password (basic authentication).

EWS (Exchange Web Services): Username/password (basic authentication) or OAuth2 using ClientID, TenantID, and a client secret.

Microsoft Exchange Online (Graph API): Microsoft Entra ID authentication via an OAuth2 connection. The connection can be configured directly in the check rule or managed centrally via Setup > Microsoft Entra ID connections and then referenced in the rule. In distributed environments, the OAuth2 connection can be created on the central site while the OAuth2 authentication process (redirect URI) is handled by a different remote site. The site used for the authentication redirect can be selected when configuring the OAuth2 connection.

This check can be configured using WATO.