Microsoft Exchange 5.5 End of Life
Support dates and upgrade guidance — rebuilt from live data.
Microsoft Exchange 5.5 reached end of life on 10 Jan 2006. It no longer receives security fixes.
Support timeline
Official dates from the Microsoft Exchange release process.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 3 Feb 1998 | — |
| End of life | 10 Jan 2006 | 20.6 years ago |
| Active support ended | 31 Dec 2003 | security fixes only after this |
| Latest release | 5.5.2653 · 1 Nov 2000 | final |
Where to go from 5.5
Recommended target: Microsoft Exchange subscription.
The newest actively supported branch is Microsoft Exchange subscription (latest release 15.2.2562.43).
Frequently asked questions
Is Microsoft Exchange 5.5 still safe to use?
Microsoft Exchange 5.5 reached end of life on 10 Jan 2006, 7,516 days ago, and is no longer covered by standard support. Running it means no guaranteed security fixes.
Can I still download Microsoft Exchange 5.5?
Yes — the final release (5.5.2653) generally remains available from vendor archives and OS package mirrors, but installing it means running software with known, unpatched vulnerabilities.
What should I upgrade Microsoft Exchange 5.5 to?
Upgrade to Microsoft Exchange subscription, the newest actively supported branch.