It is crucial to address the keyword "free" directly. GT Designer3 is a commercial software product developed by Mitsubishi Electric. It is proprietary and protected by copyright laws.
Mitsubishi has released newer versions (e.g., GT Designer3 Version 1.100+, GT Works3). If compatibility with an old GOT is your goal, contact technical support — they may provide legacy version access to license holders. gt designer 3 version 1.74 download free