Logitech must make the worst mac software anywhere. And it isn't just this version. They haven't produced a decent driver for mac since they started seven years ago. The previous times I have installed this software it's screwed up my computer pretty bad. I thought I would give this new version a try. It didn't recognize my mouse so I uninstalled it. Then half my applications wouldn't open. I ended up having to replace my framework folder from a backup, after having to boot into a separate hard drive. I'm done with Logitech.