POPcon / POPcon PRO Version History

This history applies to both POPcon and POPcon PRO.

2026

v4.10.0 (May 19, 2026) — Microsoft OAuth modernized: new public-client app registration under Servolutions IP Corporation, no client_secret shipped, PKCE-only. One-time re-authentication required for existing Microsoft OAuth accounts on upgrade. UX: prompt=select_account for multi-mailbox tenants. Proactive token refresh 5 min before expiry.

v4.9.14 (April 12, 2026) — Bugfix: OAuth token renewal now continues to work after restart. Improved: Extended logging in internals.log for OAuth events.

v4.9.12 (March 27, 2026) — Improved: Added French, Italian, Portuguese and Chinese language translations. Bugfix: Fixed Internationalized Domain Name (IDN) support for Umlauts and similar characters in domain names.

v4.9.11 (March 09, 2026) — Installs additional libraries for new version of antivirus update engine.

v4.9.9 (March 03, 2026) — Automatically cleans up list of antispam blacklist servers, removing defunct servers and updating names. Diagnostic error logging when antivirus updates don’t work.

v4.9.8 (March 02, 2026) — Bugfix: Crashes when loading a config file from a different server with OAuth references. POPconAdmin window position validation. Repaired [SPAM] tag injection function.

v4.9.7 (February 27, 2026) — Additional diagnostics for antispam checking.

v4.9.6 (February 26, 2026) — Visual C++ Library detection fix for v14+ redistributables.

v4.9.5 (January 07, 2026) — Visual C++ Library detection false error fix. New version of email handling libraries integrated.

2025

v4.9.4 (October 31, 2025) — New antivirus update process to support new ClamAV updater (PRO).

v4.9.2 (July 26, 2025) — OAuth with Microsoft servers: fixed port allocation issue by selecting ports 8080–8084.

v4.9.1 (July 17, 2025) — Fixed problem with digital SMIME signatures invalidated by X-Header modification.

2024

v4.8.12 (December 07, 2024) — AV-update fixed. Better error messages for multiple SMTP error responses.

v4.8.11 (November 21, 2024) — Bugfix: Exchange email address resolution on Windows 2022 servers. Window position fix for POPconAdmin.

v4.8.10 (November 21, 2024) — New feature: Sender address for Postmaster notifications now configurable.

v4.8.9 (November 20, 2024) — Several small improvements in the archive function.

v4.8.8 (November 19, 2024) — Upgraded AV core engine.

v4.8.7 (November 01, 2024) — Uses encrypted AV update path for better antivirus update connectivity.

v4.8.6 (October 31, 2024) — Bugfix: Antispam blacklist servers used even when found to be non-working.

v4.8.5 (October 21, 2024) — POPconAdministrator uses Roaming Profile folder to persist dialog sizes and positions.

v4.8.4 (October 17, 2024) — Roaming Profile implementation. Import of old POPcon v3 registry entries made more robust.

v4.8.3 (October 02, 2024) — POPconAdministrator persists dialog sizes and positions between sessions.

v4.8.2 (October 02, 2024) — New: X-cloud-security-recipient header supported. Retry-folder issues with antivirus software fixed.

v4.8.1 (September 23, 2024) — New: OAuth2 modern authentication for both Google and Microsoft accounts.

v4.7.18 (August 21, 2024) — Bugfix: Archive folder creation and email copying.

v4.7.17 (August 12, 2024) — Removed forced VC++ Redist installation; added warning in Admin instead.

v4.7.16 (July 24, 2024) — Better protection against double-download emails left on POP3 server.

v4.7.15 (July 16, 2024) — Auto-installs missing VC++ Redist. Less resource-intensive AV implementation.

v4.7.14 (July 12, 2024) — Auto-installs missing VC++ Redist.

v4.7.11 (June 14, 2024) — New POP3/SMTP library version for extended email header field compatibility.

v4.7.10 (June 10, 2024) — Correct error message for IMAP mail download failures.

2023

v4.7.9 (May 19, 2023) — VC++ Redistributable package installation. Debug info for .NET and VC++ redist in internals.log.

v4.7.8 (May 03, 2023) — Bugfix: Function to silently drop specific recipients.

v4.7.7 (May 01, 2023) — Bugfix: Unicode character crashes in subject lines. Archiving with/without SPAM tags. Increased AV system compatibility.

v4.7.6 (April 16, 2023) — Bugfix: Missing x64 antivirus files.

v4.7.4 (April 13, 2023) — Bugfix: Missing x64 Visual C++ redistributable library.

v4.7.3 (April 11, 2023) — Bugfix: Chilkat library startup with x64 version.

v4.7.2 (April 07, 2023) — Bugfix: Notification email template preservation for non-transferrable emails.

v4.7.1 (April 03, 2023) — Additional log details for internals.log.

v4.7.0 (April 02, 2023) — Minor changes to error handling code.

2022

v4.6.9 (June 30, 2022) — Timeout extended for POP3 server connections. PRO: Antivirus disabled state now reported correctly.

v4.6.8 (June 05, 2022) — Bugfix: Antivirus updates.

v4.6.2 (January 26, 2022) — New: X-FORWARDED-FOR header support for catch-all mailbox distribution.

v4.6.1 (January 20, 2022) — Bugfix: Antivirus data files update not working on some client installs.

2021

v4.5.1 (July 03, 2021) — Multiple bugfixes and improvements: archive exception handling, antispam list sorting, resizable configuration forms, CTRL+A account selection, rule sorting fixes.

v4.0 (April 11, 2021) — New: Parallel download of multiple POP3/IMAP mailboxes (PRO). Improved download speed. TLS1.2 encryption support.

Earlier Versions

v3.94 (November 17, 2016) — Long file names in MIME headers now detected correctly for RULES.

v3.93 (October 16, 2015) — Timeout problems during email transfer to Exchange 2013 solved.

v3.92 (April 20, 2015) — Bugfix: Inefficient memory management for list of emails kept on POP3 servers.

v3.91 (April 17, 2015) — Updated to OpenSSL v1.02a library for improved SSL speed and stability.

v3.90 (March 25, 2015) — SSL connections speed up by caching connection parameters.

v3.89 (March 10, 2015) — New OpenSSL Library v1.02 for faster SSL connections.

v3.84 (April 11, 2014) — Using OpenSSL v1.0.1g with ‘Heartbleed’ fix.

v3.81 (June 13, 2013) — X-Orig-To header support. ESET antivirus greylisting support with automatic retries.

v3.77 (April 20, 2012) — Multiple new features: 0-byte email removal, scanner/fax device support, per-account archiving, 554 error handling.

v3.74 (September 30, 2011) — Continuous downloading with 0-minute cycle time.

v3.70 (September 08, 2008) — Windows 2008 support. Exchange 2007 extended support. Archive function.

v3.60 (December 07, 2006) — Per-mailbox display names. Separate antivirus check pass. X-POPCON-SPAMCHECK header.

v3.50 (July 28, 2006) — Lotus Notes Domino variant. Blacklist/whitelist import/export. Read receipt removal.

v3.20 (September 19, 2005) — IMAP and IMAP-SSL mailbox support. New antivirus engine.

v3.00 (April 22, 2005) — Catch-all function. POP3 over SSL. Regular expression support.

v2.91 (February 09, 2004) — User-defined blacklists/whitelists. Rules engine phrase search.

v2.80 (August 01, 2002) — Antispam using blacklist-DNS servers (PRO).

v1.90 (February 09, 2010) — First published version after beta phase.