Microsoft to address issues and introduce new functionality in Exchange Server March 2024 Security Update (SU) Hotfix Updates (HU) for April 2024 This update applies to the following Exchange Server versions:
Exchange Server April 2024 New Features
Exchange Server April 2024 HU, elliptic curve cryptography (ECC) certificates support and for Outlook for web and ECP hybrid modern authentication (HMA) offers support.
Hybrid Modern Authentication (HMA) for OWA/ECP
From April 2024 HU OWA/ECP a HMA is also supported. This feature requires Exchange 2019 CU14 + April 2024 HU or later.
Exchange Server April2024 Resolved Issues
- Fixed Download Domains issues not working after installing SU, March 2024.
- Fixed the issue where “This document cannot be opened” error occurred in OWA after installing SU March 2024.
- March 2024 Outlook cache mode search error after installing SU
- Fixed OwaDeepTestProbe and EacBackEndLogonProbe failures after installing March 2024 SU.
- Fixed an issue where permissions could not be edited in ECP.
- Unread envelope icon not shown in Outlook after installing March 2024 SU (Note: This issue has been resolved for new emails after April 2024 HU or later)
- March 2024 Fixed the issue where the My Templates plugin was not working after installing SU.
- Fixed an issue where published calendars would not work with the error “This calendar does not exist” after installing March 2024 SU.
Problem Still Needing to Be Solved:
- Printing calendars in OWA does not work unless the CTRL+P keyboard shortcut is used. This will be addressed in a future update.
Exchange Server April 2024 Hotfix Patch Update FAQ
- We installed March 2024 SU. Should we install April 2024 HU? The April 2024 HU is an optional update, but it also adds HMA support for ECC certificates and OWA/ECP. If you have installed the March 2024 SU and have not experienced any known issues and do not need the new functionality, you can choose not to install the April 2024 HU and wait for a future SU (which will include known issue fixes from the April HU).
- We haven't installed the March 2024 SU yet. Do we need to install the March SU first to install the April 2024 HU? April 2024 HU includes the same security updates as March 2024 SU, while also addressing known issues with March 2024 SU. If you have not installed March 2024 SU, you can install April 2024 HU directly and skip March 2024 SU.
- Our Exchange servers are automatically updated via Windows/Microsoft Update. We have already installed the March 2024 SU. Will our servers automatically install the April 2024 HU? April 2024 HU will appear as an optional update for your servers.
- Does the April 2024 HU contain any security updates that are not included in the March 2024 SU? The security content of the April 2024 HU is the same as the March 2024 SU.
- Will the two new features (ECC certificates support and HMA for OWA/ECP) be included in future updates or do we need to install this specific HU? These two features introduced in April 2024 HU will be included in subsequent updates for Exchange Server.
- Can the April 2024 HU be lifted if necessary? Yes, HUs, like SUs, can be removed.