Exchange Online Message Recall Updates

After the launch of cloud-based message recall for Outlook for Windows in April 2023 (see) Cloud-based message recall for Exchange Online), we have been continuously working on improvements and enhancements, including: Outlook on the web support And an improved experience when retrieving shared mailbox messages. Today, we are excited to announce several additional updates and improvements based on customer feedback, now available to all Exchange Online customers.

• Optional recall notification for recipients
• Maximum recoverable message lifetime
• External round-trip routing support

Optional recall notification for recipients

Previously, when a message was recalled, it would be automatically deleted from the recipient’s mailbox, which was sometimes confusing for users. Recipients who had seen or read the message before it was recalled could be confused that the message was gone. While senders often prefer to be discreet about recalls, some recipients were confused by the automatic deletion. To reduce recipient confusion, tenant admins can now enable recall notification emails to recipients when a message is recalled. This feature is disabled by default, but can be enabled in two modes.

• For all recovered messages
• Only read messages are retrieved

When enabled, the relevant recipients of a recalled message will receive an email notification informing them of the recall. For example:

Administrators can configure recall notifications for recipients in the Exchange admin center (Settings > Mail Flow).

Administrators can also configure these settings using Exchange Online PowerShell.

Set-OrganizationConfig -MessageRecallAlertRecipientsEnabled [$False | $True]

Enables or disables message recall notifications for recipients. Setting this parameter to $True enables notifications, while setting it to $False (default) disables notifications.

Set-OrganizationConfig -MessageRecallAlertRecipientsReadMessagesOnlyEnabled [$False | $True]

-When the MessageRecallAlertRecipientsEnabled parameter is set to $True, this cmdlet enables administrators to specify whether recall notifications should be sent only for read messages. Setting this parameter to $True enables notifications only for read messages, while $False (the default) enables notifications for read and unread messages.

Maximum recoverable message lifetime

Previously, messages could be recalled regardless of age. Customers have been asking for the ability to limit recall of older messages, such as messages sent more than 30 days ago. The new Maximum Retrievable Message Age setting allows this, with a default of 365 days. Tenant admins can configure this to be between 5 minutes and 10 years.

This can be done in the Exchange admin center (Settings > Mail Flow).

You can do this using Exchange Online PowerShell.

Set-OrganizationConfig -MessageRecallMaxRecallableAge [DDDD.HH:MM:SS]

If a sender attempts to recall a sent message that is older than the allowed age, the sender will be notified that the message is too old to be recalled.

External round-trip routing support

By design, message recall does not support recalling messages sent outside the Exchange Online service boundary. However, some administrators route intra-tenant mail (where the sender and recipient are in the same tenant) from Exchange Online to a third-party service or on-premises system for further processing, and then back to Exchange Online for delivery. Previously, recall failed in this scenario.

Today, we are excited to announce that Message Recall now supports recalling intra-tenant messages that have been routed externally and then delivered back to Exchange Online.

All three updates are now available for Exchange Online tenants. We hope you find these improvements useful and look forward to your feedback.

Kevin Shaughnessy