As always, this upgrade is free for all users with a current software maintenance.
The full list of changes since the latest official release (4.7.4.254) is as follows:
// New to VersionNumber = '4.7.6.262';
{TODO -cNew : Replaced the GeoIP.dat country lookup with a new database format - geoip.sqlite. This should improve misdetected Countries when perfoming lookups under heavy inbound loads. Requires the inclusion of the appropriate x32/x64 sqlite3.dll file included in both the binary-only and the full installer distributions}
{TODO -cFix : The Blacklist Country blacklist was showing a "0" instead of the correct, real-time number of email blocked for each country}
{TODO -cFix : Disabled the reporting of log events from the external AV updater SpamFilterAVUpdate.exe to SpamFilter as they were causing Access Violations. Logs from SpamFilterAVUpdate.exe are still being logged in their own logfiles}
// New to VersionNumber = '4.7.5.258';
{TODO -cFix : Fixed a regression error introduced back in 2016 for these errors that might appear in the logfiles and that could in some rare cases crash SpamFilter: "Access violation at address 000000000040EBDF"}
{TODO -cNew : Added a new "X-SF-SPF-Result" header in the emails indicating the result (pass/none/neutral/fail/softfail/error) of the SPF checks. It's to be noted that sometimes SPF checks are not performed if other filters have already detected the email to be spam before the SPF test is executed, or if the email is whitelisted}
{TODO -cNew : Added a new "X-SF-SPF-Result-From-Header" header in the emails indicating the result (pass/none/neutral/fail/softfail/error) of the SPF checks performed on the email address specified in the "From:" header. It's to be noted that sometimes SPF checks are not performed if other filters have already detected the email to be spam before the SPF test is executed, or if the email is whitelisted}
// New to VersionNumber = '4.7.5.257';
{TODO -cNew : Added a new "forcedelete" suffix to prevent spam emails from being quarantined anywhere the "nondr" and "null" suffixes are supported}
{TODO -cNew : SpamFilter is now scanning emails that are being force-delivered out of the quarantine for viruses. If SpamFilter detects a previously undetected virus in the archived email, the email will not be delivered. Instead the database quarantine record for that email will be updated to show it was stopped becuase of a virus. If at that point the user really wants the email force-delivered, they can re-request delivery. If an email is quarantined due to a virus, but the user decides to force-deliver it, it will be delivered}
// New to VersionNumber = '4.7.4.255';
{TODO -cFix : The SURBL filter was not checking URLs starting with https}
{TODO -cNew : Eliminated an extra redundant scan of the email for domains while checking the SURB and the 0-day filters}
{TODO -cFix : Resolved issue with MySQL (MS SQL Server is not affected) when quarantining emails having emojii or other encoding if the SpamFilter database server has a default character set/collation of utf8mb4 }