Pasquale Pillitteri reported the story. The poster's account, the vote count and the comments are the poster's claims or the report's. We haven't independently verified them.
What the poster says happened
According to the report, Meta4X's first home Exchange server ran Exchange 5.5 on Windows NT 4 in 1999. They then followed each release, which makes eight versions:
- Exchange 5.5
- Exchange 2000
- Exchange 2003
- Exchange 2007
- Exchange 2010
- Exchange 2013
- Exchange 2016
- Exchange 2019
The poster says the real mailboxes moved to Microsoft 365 a couple of years ago. The home server stayed on as a relay for printers, NAS boxes, UPS units and monitoring tools that send alerts by email. The post reportedly drew about 690 votes. One comment included an archive photo of a 2003 "server" with the motherboard cable-tied to its shipping box.
The report cautions against guessing at a motive, and that's sensible. The post doesn't say whether the end of support or the move to subscription licensing mattered more.
Why Exchange 2019 is a liability now
Microsoft's Exchange team documented the support timeline in several places:
- Exchange Server 2016 and Exchange Server 2019 reached end of support on October 14, 2025.
- Existing installations continue to run after that date.
- Users no longer receive bug fixes, security fixes or time zone updates.
- Microsoft's recommendation is to migrate to Exchange Online or upgrade to Exchange Server Subscription Edition (SE).
Microsoft's own lifecycle listing for Exchange 2019 shows an extended-end date of October 15, 2025. That is a time-zone artifact of the listing, and Microsoft's Exchange-specific communications consistently say October 14.
The report also describes an Exchange-specific paid ESU program ending October 13, 2026, and licensing and price changes for SE. I couldn't confirm either in the Microsoft documentation I checked. One outside source, the New Jersey Cybersecurity and Communications Integration Cell, said ESUs would not be offered for these versions. Treat the ESU claims with caution and check your own agreement.
The upgrade path for admins who keep Exchange
If you still need Exchange on-premises, Microsoft's guidance is fairly simple:
- If you run Exchange 2019, upgrade in place to Exchange Server SE.
- If you run Exchange 2016, do a legacy (side-by-side) upgrade to Exchange Server SE.
- If Exchange 2013 or earlier is still in the organization, remove it before installing Exchange 2019 CU15 or upgrading to SE.
The in-place path from 2019 is technically low drama. Microsoft's documentation says SE is essentially the same as Exchange 2019 CU15 with some extra tweaks. Microsoft's Learn pages say the SE RTM differs from CU15 only in the license agreement, the product name and the build number. The in-place upgrade is supported from Exchange 2019 CU14 or CU15. As Microsoft's "What's new" page puts it, in-place upgrades from versions earlier than Exchange 2019 are not supported. Office 365 IT Pros noted that the harder question for customers is understanding exactly what licenses they need to run SE, especially in hybrid environments.
Why "just switch it off" isn't general advice
Meta4X's setup was simple. The mailboxes were already in the cloud, and what remained was SMTP forwarding. Many businesses are not in that position.
Microsoft's end-of-support roadmap includes a warning. If you move mailboxes to Microsoft 365 but keep using Microsoft Entra Connect to manage users in Active Directory, you must keep at least one Exchange server. Without one, you can't change Exchange recipients in Exchange Online, because on-premises Active Directory remains the source of authority. Microsoft's recommended fix is to migrate the mailboxes and upgrade to SE. After that, decommission the old 2019 or 2016 servers.
Some commenters on the post reportedly advised powering the machine off rather than uninstalling Exchange. They said removal can alter Active Directory schema attributes needed for a hybrid setup. That's anecdotal advice from commenters, not a Microsoft procedure. If you have Active Directory or a hybrid deployment, follow Microsoft's decommissioning documentation for your own configuration.
Postfix as a relay: what it is and isn't
Postfix's project page says it is Wietse Venema's mail server that began at IBM Research as an alternative to Sendmail. The project aims to be fast, easy to administer and secure. Built from source, it runs on Unix-like systems including Linux. Distributions also package it, so you can update it through your OS's normal channels. The report puts the first release in December 1998 and gives the license as IBM Public License or Eclipse Public License. I didn't verify either detail.
For this use case, the difference in scope matters:
- A printer, NAS or UPS sends an SMTP message to the relay.
- The relay forwards it to the destination service, such as Microsoft 365.
- No mailboxes, calendars or shared contacts are involved.
That narrow job is why Postfix is a plausible replacement here, and it isn't a claim that Postfix replaces Exchange as groupware. It also doesn't make delivery effortless. You still have to configure the sending devices and the onward route. You also have to keep the Linux host patched, and the report adds that Microsoft 365 delivery needs sensible SPF and DMARC handling.
The report also says Microsoft's licensing FAQ requires an Exchange license for on-premises SMTP forwarding. I couldn't verify that here, so check the licensing terms before assuming a relay is free either way.
What to do with an out-of-support Exchange box
Use this as a quick triage:
- Does it host mailboxes? Plan the move to Exchange Online or SE now. Every month without patches adds risk, especially if the server is reachable from the internet.
- Is it only a relay? Ask whether it needs to be Exchange at all. A small MTA or a cloud-side connector may do the job with a much smaller attack surface.
- Is it part of a hybrid setup? Check whether Entra Connect and on-premises Active Directory still depend on it for recipient management before you decommission anything.
- Is it a lab or test box? Without patches it's still a risk if it's exposed, so keep it off the internet.
The story is charming, and the box tied to cardboard is a fine mascot for homelab culture. The practical takeaway is more sober. Exchange 2019 can no longer receive fixes. Replacing a relay-only role with a simple MTA is reasonable, but decommissioning a hybrid-connected Exchange server needs planning.