1. Before uninstalling ExtendSim, be sure to revoke the license using the Help > Revoke License command (or the Help > Deactivate ExtendSim command if prior to 10.0.5)..

2. Use the Windows Settings > Apps and Features to uninstall ExtendSim.

3. Then delete the two folders: Documents\ExtendSim and Program Files\ExtendSim. (These two folder are left after uninstalling because their contents were created after installation so the uninstaller doesn't know about them.)