FactSage patch required to ensure operation in 2026

This issue brings an important announcement that affects all users of FactSage: without the newly released patch, all versions will cease to operate on January 1, 2026. Please review the instructions below carefully and update your installation as soon as possible.

This issue’s content:

1. Action required: Mandatory FactSage patch for 2026
2. FactFlow & FactProSim for client network installations
3. Farewell to Gwen and Phil Spencer
4. New application study: Optimizing Copper extraction

1. Action required: Mandatory FactSage patch for 2026

Summary (FactSage 7.0–8.4)

What: Starting Jan 1, 2026, FactSage will not start without a revised patch. This revised patch supersedes earlier database-related fixes and is required, even if a database patch was installed in November. 

Action: Install the revised patch using the Installation Guide linked below.

When: Installation can be done at any time before or after Jan 1, 2026 (recommended before end of 2025).

An internal malfunction in a database expiration mechanism will prevent all versions of FactSage from starting as of January 1, 2026. 

Depending on your version of FactSage, please refer to the information below for the necessary next steps. We apologize for the inconvenience this may cause.

FactSage 7.0 - 8.4

A revised patch (December 2025) is now available. Detailed, up-to-date installation instructions are provided via the button below, which links to the centrally maintained installation guide. This ensures that both the patch and the installation instructions are always up to date.

This issue is not related to licensing or security, and no reinstallation of FactSage is required.
The patch only updates the affected database components.

If the patch is not installed, FactSage will no longer start as of January 1, 2026.
However, you can install the patch at any time thereafter, and FactSage will resume normal operation immediately.
Users who do not need to run FactSage on January 1 can safely wait until after the holiday period to install the patch.

We are currently working on integrating this patch into new FactSage installations so that future installations will include the fix by default.

FactSage 6.3 - 6.4

If your latest FactSage version is 6.3 or 6.4, please contact us directly via our ticket system. Select the help topic: "FactSage not starting/Dec 2025 error (versions 6.3–6.4)" so we can provide individual assistance.

Important reminder

Please note that FactSage.com is the authoritative source for official FactSage patches, known issues, and technical notices. The revised patch itself is provided by our Canadian partners at Thermfact/CRCT and published there accordingly.

2. FactFlow & FactProSim for client network installations

— Updated information provided by our Canadian partners at Thermfact/CRCT —

The FactFlow and FactProSim add-ons were originally only accessible from standalone installations. However, it is now possible to run these add-ons on client installations in network environments.

3. Farewell to Gwen and Phil Spencer

When someone who helped shape an entire field retires, it’s a significant milestone. When two such people retire together, it’s the end of an era. In this blog post, we bid farewell to Gwen and Phil Spencer as they begin their well-deserved retirement:

4. Optimizing copper extraction – Part I

Our team has published the first part of a new article series: “Optimizing Copper Extraction: Integrated Pyrometallurgical Modelling with ChemApp for Python – Part I.”

The study demonstrates how integrated thermodynamic calculations can support process development in complex pyrometallurgical flowsheets and introduces key concepts for building transparent, reproducible simulations with ChemApp for Python.

Read more:

This month’s newsletter focuses on ensuring uninterrupted operation of FactSage in 2026 and beyond. Please update your installation and make sure your colleagues are aware of this requirement.

We understand that handling technical updates at the end of the year is inconvenient. Despite this, we hope you have a calm and productive end to 2025.

As always, please feel free to contact us if you have questions, encounter issues, or need assistance with FactSage, ChemApp, or any of our tools. 

Your GTT-Technologies Team