We are excited to announce the general availability of Exchange Server Subscription Edition (SE). This release continues Microsoft’s long tradition of enabling customers to provide enterprise email s...
Updated Aug 06, 2025
Version 5.0
Blog Post
I see and hear with great bitterness the great instability assumed by the EXCHANGE On Premise platform after the updates made and I also make known other problems that I am experiencing after having made the decision to upgrade EXCHANGE 2016 to 2019 to adapt the entire platform with Mailboxes and Public Folders to the latest version "Exchange Server Subscription Edition (SE)".
Despite having always done the necessary updates, we find ourselves with the following situation: Exchange Server 2019 with all mailboxes except the modern mailboxes of the public folders which remain on Exchange Server 2016 as the cmdlets do not work and for months I have not been able to have a suitable contact for MICROSOFT SUPPORT or even purchase adequate assistance, not even via PRIVATE MICROSOFT ACCOUNT.
So, here's the current state of affairs:
• Version Misalignment and Lack of Security: The Exchange Server 2019 release is CU13 with the November 2024 Security Update (build 15.2.1258.38). This release is severely corrupted, preventing any updates or repairs, exposing the system to potential security vulnerabilities. Support for the base CU13 release expires on October 14, 2025.
• Public Folder Migration Blocked: Server corruption prevents the creation of a new public folder mailbox with primary hierarchy. This is essential to migrate public folders from the Exchange 2016 server and decommission it, as originally intended.
• Upgrade and Repair Failure: Attempts to upgrade the Exchange Server 2019 server to CU15 have failed due to a missing critical installation file (exchangeserver.msi). Repair attempts (/m:RecoverServer) were also blocked because the setup detected Exchange roles already installed, despite the corruption.
• Operational Stall: The Exchange 2019 server is in a state that prevents the completion of essential maintenance and migration operations. This situation makes the server a roadblock for decommissioning the hybrid environment (2016-2019) and completely migrating to a more modern and better supported infrastructure.
• Resolution Strategy: Due to the irreparable nature of the corruption, the only viable solution is a complete rebuild of the Exchange 2019 infrastructure, hoping to install a new, clean "Exchange Server Subscription Edition (SE)" server in parallel if I do not receive any support from the Microsoft vendor, given their policy of being absent from the product and their professionals. I hope this strategy will resolve the current issue and ensure a stable and more secure environment in the long term. I'm wondering, will Microsoft force me to license the new Exchange Server (SE) or will they allow me to migrate one of their non-upgradeable products within 30-90 days?
Thank you for your attention.
I'm updating the situation after receiving the following information yesterday: Released: August 2025 Exchange Server Security Updates
This information has made me realize that, in my situation, the best course of action for security and mitigation is to "disable all Exchange-specific administrative profiles" as the best immediate action to protect the entire Exchange infrastructure.
This approach is crucial because:
- It Reduces the Attack Vector: Many critical and high-severity vulnerabilities, such as the recent CVE-2025-53786, require an attacker to already have administrative access to exploit them. Disabling these accounts will make it much more difficult for a potential attacker to gain the privileges needed to compromise the entire environment.
- It Limits Risk: In an unpatchable system with known vulnerabilities, every active administrative account represents a risk point. Keeping them disabled minimizes the possibility of their being compromised.
- Supports Planning: This security measure allows you the time you need to plan and implement the long-term solution (building a new, clean server) without the constant pressure of impending risk.
...and hopefully in the meantime I can also get support from Microsoft with fair compensation in this regard
...and hopefully I get through this without any disaster. ¯\_(ツ)_/¯