In Microsoft Exchange Online, when a Data Loss Prevention (DLP) rule triggers an action to forward a message for approval to the sender's manager, several outcomes can occur based on the manager's response or lack thereof. The configuration you described pertains to a DLP policy rule action where messages that trigger certain conditions are sent to the sender's manager for approval oai_citation:1,Common message approval scenarios in Exchange Online. This action operates effectively if the sender's Manager attribute is defined in the system; otherwise, the message gets delivered to the recipients without moderation oai_citation:2,Mail flow rule actions in Exchange Online | Microsoft Learn.
Now, regarding your specific queries:
- Unresponded Approval Requests: If the manager doesn't approve or deny the message within a specific timeframe (the expiration time is two days for Exchange Online), the sender will receive an expiration message. The processing of expired moderated messages runs every seven days, meaning a moderated message can expire anytime between two and nine days post the approval request oai_citation:3,Common message approval scenarios in Exchange Online | Microsoft Learn.
- Backup Approver or Fallback Mechanism: For setting up a multi-level approval chain, you could create multiple mail flow rules, each for a different level of approval. For instance, a message could first be sent to a manager for approval, and then to a compliance officer for a second approval. Each rule will detect the same patterns in the messages and forward them to the respective approvers. However, if any of the moderators in the chain reject the approval request or if any of the requests aren't approved within the expiration time, the sender receives the corresponding rejection or expiration message oai_citation:4,Common message approval scenarios in Exchange Online | Microsoft Learn.
This multi-level approval setup could serve as a fallback mechanism, ensuring that another individual reviews the message if the primary approver (e.g., the manager) doesn't respond within a stipulated time. Yet, the specifics would depend on how the mail flow rules are configured in your organization's Exchange Online setup.
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