hMailServer 6.2.2

Released 14 June 2026 6.2 series

This is not the current release. hMailServer 6.3.3 is the one to install unless you need this exact version.

Downloads for 6.2.2

Windows

Windows 10 (version 1607 or later) and Windows 11, or Windows Server 2016 and newer; 64-bit only. Run the installer as an administrator: it upgrades an installation older than this version in place, and it cannot go backwards — an older server refuses a database a newer one has upgraded, so back up the database and the data directory first. It is not Authenticode-signed, so Windows names an unknown publisher and SmartScreen warns before it will run it.

  • hMailServer-6.2.2-x64.exex64 · 79.5 MB
    Download
    SHA-256beea6cd7f189…a6d56833

What’s new in 6.2.2

This release pairs the v6.2.2 server with a substantially upgraded Control Panel (the modern .NET 8 admin app). The server is unchanged from the original 6.2.2; all new work below is in the Control Panel and is bundled in this installer.

Full release notes for 6.2.2 4 sections

Server (6.2.2) — authentication hardening

  • Full RFC 4013 SASLprep for non-ASCII SASL credentials: RFC 3454 mapping, Unicode NFKC normalization, the complete prohibited-output tables (C.2.1/C.2.2/C.3–C.9), and the RFC 3454 §6 bidirectional check. NFKC is a no-op on ASCII, so existing credentials are unaffected.
  • Automated RS256 (public-key) OAuth2 bearer-token regression coverage over POP3 and SMTP, including a tampered-signature rejection check.

Control Panel — UX/UI polish

  • Cached settings pages now refresh on navigation (no stale values).
  • Domains aliases / distribution lists show real empty and error states instead of a silent blank list.
  • Search/filter on the long list pages (Domains, Accounts, Rules, Delivery queue, TCP/IP ports, SSL certificates, IP ranges, Routes).
  • Confirmation prompts before deleting aliases, distribution lists, list recipients and incoming relays.
  • Numeric input validation with inline feedback in the Domain/Account/Route dialogs (bad values are reported, not silently dropped).
  • Standardized empty/error placeholders across the list and grid pages.
  • Follows the OS light/dark theme by default (and tracks live OS changes) until you pick a theme manually.
  • The overloaded Advanced navigation group is split into Security, Network and Maintenance.
  • Dialog inputs unified to the modern Wpf.Ui text style.
  • Global exception handler: unhandled errors are logged to %LOCALAPPDATA%\hMailServer\ControlPanel and you are offered a restart.
  • Responsiveness: lower minimum window size and an adaptive sidebar / Connect card for small, zoomed or RDP sessions.

Control Panel — AV & security extensibility

  • Anti-virus page: "Test ClamAV connection" and "Test ClamWin scanner" buttons (live test via the server), a "Test custom scanner" check, a custom-scanner preset picker for common engines (Microsoft Defender, Sophos, ESET, Bitdefender, Kaspersky), and a ClamWin auto-detect.
  • Event scripts page: an "Insert template" picker with ready-made OnAcceptMessage handlers (external AV/DLP scanner, SIEM/Slack/Teams webhook, external HTTP API verdict).
  • New "Advanced hardening" page exposing previously-hidden hMailServer.INI knobs (greylisting expiration, SpamAssassin/ClamAV scanner timeouts, DNS cache/server/DNSBL timing, authenticated-user IP replacement, AUTH disable list, X-AuthUser/X-OriginalRcptTo headers, blocked-IP hold, envelope-from rewrite, and a password-hash-algorithm picker: Argon2id/PBKDF2/SHA-256/MD5/Blowfish).
  • Account dialog: live password-strength indicator and a confirmation before saving a weak password.

Control Panel — accessibility & automation

  • Screen-reader names on icon-only controls, search boxes, the navigation tree and the content host.
  • Every navigation node and data-driven settings editor now carries a stable AutomationId; the in-app UI-automation quality audit improved from grade F to grade A.

Builds clean (0 warnings, 0 errors). The Control Panel requires the .NET 8 Desktop Runtime (bundled by the installer).

Release facts

Version
6.2.2
Packages
1Windows, x86-64
Installer SHA-256
beea6cd7f189…a6d56833hMailServer-6.2.2-x64.exe

Every file in 6.2.2

Full SHA-256 of each file as recomputed on this server. Nothing in this release is signed — the signing workflow came later — so the hash above is this server’s own recomputation rather than a check against something the project signed.

FileWhat it isSizeSHA-256Signature
hMailServer-6.2.2-x64.exeWindows installer · x6479.5 MBbeea6cd7f18961bd00c2cc78b520d7a14b12aa1c25840fa142eeea92a6d56833