I understand you're looking for information about downloading CODESYS 2.3.9, but I need to provide an important clarification and some helpful guidance.

The full story:

CODESYS 2.3.9 is an older version of the popular IEC 61131-3 programming system for industrial controllers. This version was widely used with legacy PLCs from manufacturers like Wago, Beckhoff, Festo, and others.

Important legal and practical considerations:

  1. Official sources only – CODESYS is proprietary software owned by CODESYS GmbH (formerly 3S-Smart Software Solutions). Legitimate downloads are only available through their official website or authorized distributors.

  2. No direct download links – I cannot provide direct download links because:

    • Old versions like 2.3.9 are generally not publicly available on the official site anymore
    • Sharing unofficial links could lead to malware, legal issues, or unsupported software

  3. What you should do instead:

    • Contact CODESYS directly – Ask their support if legacy versions are available for specific maintenance contracts
    • Check your PLC manufacturer – Many vendors (Wago, Beckhoff) provide customized CODESYS versions with their hardware
    • Use newer versions – CODESYS V3 is the current platform, though it's not backward-compatible with V2.3 projects
    • Check archive.org – The official CODESYS download area might have historical versions if you have proper credentials

  4. Security warning – Downloading CODESYS 2.3.9 from third-party sites (file sharing, torrents, unknown forums) carries high risks of malware, especially given its age and lack of security updates.

If you absolutely need V2.3.9 for legacy hardware maintenance, your best legal path is to contact CODESYS GmbH support or your original equipment vendor with your license information.

Would you like guidance on migrating legacy projects to CODESYS V3 instead, or help finding official support channels for your specific hardware?

Where to Download CODESYS 2.3.9

The official source is the CODESYS Store (formerly the CODESYS Forge). Here is the direct path:

  1. Go to the official CODESYS website: www.codesys.com
  2. Navigate to Downloads → Archive → CODESYS 2.3.
  3. Select CODESYS 2.3.9.x (the latest patch version is typically 2.3.9.63 or similar).

⚠️ Beware of third-party sites: Many untrusted websites offer “cracked” or “free” versions. Always download from the official CODESYS archive to avoid malware. A free license for 2 hours of runtime (for testing) is included; full licenses must be purchased from your PLC manufacturer.

Introduction

In the rapidly evolving world of industrial automation, newer is not always better. While CODESYS (Controller Development System) has released modern versions like V3.5 and V3.5 SP19, a significant portion of the manufacturing sector still relies on older, proven systems. Among these, CODESYS 2.3.9 stands out as a stable, reliable workhorse.

Whether you are maintaining a legacy production line, supporting a classic PLC (Programmable Logic Controller) from brands like Wago, Beckhoff, or Festo, or simply learning IEC 61131-3 languages on older hardware, finding a legitimate and safe CODESYS 2.3.9 download is crucial. This article provides everything you need: where to find it, how to install it, compatibility notes, and alternatives.

Installation Steps

  1. Disable antivirus temporarily (the installer contains a kernel-mode PLC runtime that can trigger false positives).
  2. Run the installer as Administrator.
  3. Select installation type – Choose “Complete” to install:
    • CODESYS Development System
    • Visualization tools
    • Target support package installer
    • PLC Win32 (soft PLC for simulation)
  4. Allow device driver installation – When prompted, accept the installation of the “CODESYS Gateway” (a service that connects the IDE to runtimes).
  5. Finish and restart – Reboot to ensure the Gateway service starts properly.

4. Internet Archive (Wayback Machine)

As a last resort, the Internet Archive has snapshots of the old CODESYS FTP server. Use with caution – verify file hashes (MD5/SHA256) if available.

Post: Where to download CODESYS 2.3.9

Looking for CODESYS 2.3.9? CODESYS 2.x is an older major version and is no longer the current release; many vendors and the official CODESYS Group site now focus on CODESYS 3.x. If you specifically need 2.3.9 (for legacy controllers, project compatibility, or reproducible builds), here’s where to look and what to keep in mind.

3.2. Third-Party Vendor Portals

Because CODESYS is a "white-label" product sold to hardware manufacturers, the most reliable source for CODESYS 2.3.9 is often the specific hardware vendor's website.

  • Wago: Wago maintains an extensive legacy download center where specific builds of CoDeSys (often packaged with Wago I/O libraries) are hosted.
  • Eaton / Moeller: Similar legacy support pages often host "XP-Pro" or "Galileo" versions of the software which are based on CODESYS 2.3.x.

Security Advisory: Avoid downloading CODESYS 2.3.9 from unverified third-party aggregators (general software download sites). Executable files from these sources may be unpatched or contain malware. Always prioritize vendor-hosted files or the official CODEYS Store archive.