Last Updated: April 20, 2023
ISSUE
Outlook Mobile fails to delete a cancelled instance from a recurring meeting. Impact is limited to On-premises Cloud Cache accounts. Users with cloud-based mailboxes are not impacted.
DETAILS
When an organizer cancels one occurrence of a recurring meeting in Outlook Mobile, the rest of the series may show as "Tentative" on the attendee's calendar, and an additional invite may be sent out. Additionally, when deleting an instance of the series in Outlook Mobile, the occurrence may not be deleted from OWA, making the cancellation appear as if it never worked.
STATUS: INVESTIGATING
The Outlook and Exchange Online teams are investigating why changes for meeting series cancellations made in the Outlook for iOS and Android apps fail to replicate from Exchange Online to On-premises Exchange. We will update this topic when we have more information about any potential future changes.
WORKAROUND
The impacted recipient can use Outlook on Windows (Outlook Desktop) or the Outlook Web Client (OWC, OWA) to remove the exception that failed to delete properly with Outlook Mobile.