: Trimble has authorized resellers around the world. Purchasing from these resellers ensures you get a legitimate license.
Back in 2016, SketchUp Pro used a two-part credential system to activate the software: sketchup 2016 license key and authorization code
Click Add License or OK to complete the activation. 3. Troubleshooting & Support Anyone got a trial key for SketchUp Pro 2016? : Trimble has authorized resellers around the world
If you encounter issues with your SketchUp 2016 license key and authorization code, here are some troubleshooting tips: sketchup 2016 license key and authorization code
Most modern extensions (Plugins) require a newer Ruby API version than what SketchUp 2016 provides. Modern Alternatives