What the upgrade involved

No database change. The schema stays at version 6005. Issue #18 is not fixed and remains open, see #20.

All four sequence-set parsers now resolve * on either side of a colon and normalise descending ranges, so 3:1 is the same set as 1:3, per RFC 3501. Twelve regression tests cover it, all twelve failing against 6.2.14.

Also fixed:

• Restoring messages emptied the live data directory before checking the backup's message store existed. A settings-only backup restored with the messages option ticked, or a failed extraction, left an empty data directory and the only copy of the mail in a GUID-named temporary folder. It now checks first.
• A message whose file could not be read hung the outbound connection after the remote answered 354, idle until the client timeout of up to ten minutes, then re-queued and repeated. It now fails immediately. Only a genuinely missing file fails the delivery permanently.
• BDAT exact-length reads padded short chunks with NUL bytes. A sender announcing BDAT 100000 LAST that vanished after 40,000 octets had the truncated message delivered as complete.
• DKIM signing hashed the header name in lower case while writing it capitalised (upstream PR #530), so signatures using simple canonicalization failed strict verifiers.
• Several paths left files with no database row: rejected POP3 RETR, header rewrites leaving .eml.tmp, downloads with no local recipient, unsendable bounces. The account cache had no size cap.
• ManageSieve now disconnects after three failed authentication attempts and registers them with auto-ban. STATUS (RECENT) reported the selected folder's count for every folder.
• Settings configurable only in hMailServer.ini gained Control Panel pages: authentication, administrative access, DNS resolver, web services and autoconfiguration, and the consistency scan results.

Full release notes, checksums and signatures