Symptoms
If you're using Public Folder, and you've configured Extended Protection, you can no longer modify the permissions through Microsoft Outlook. You can fix this issue by following the steps that are outlined in Extended Protection doesn't support public folder client permissions management through Outlook. However, after you apply this fix, incorrect Access Control Entry (ACE) is modified or removed.
Resolution
To fix this issue, install the following security updates:
- Description of the security update for Microsoft Exchange Server Subscription Edition RTM: August 12, 2025 (KB5063224)
- Description of the security update for Microsoft Exchange Server 2016: August 12, 2025 (KB5063223)
- Description of the security update for Microsoft Exchange Server 2019: August 12, 2025 (KB5063222)
- Description of the security update for Microsoft Exchange Server 2019: August 12, 2025 (KB5063221)