I bought 3 copies of the Pro version. I successfully installed on 2 PCs (1 Win 7 Home Premium, 1 Win 7 Pro). And, updated to the latest version. No issue. For the 3rd PC, running Win 7 Home Premium, after install, Win startup screen hangs. I could see the Win desktop screen and all the apps. I could move the mouse around. But when I pointed the mouse to the status bar (bottom screen), the mouse cursor changed to a rotating circle. I could not click on any quick launch icons. I could not click on the Win Start either. There is nothing I could do except to force it to shutdown. However, when I booted to the Safe mode, win worked. But win won't load in normal startup. So, while in Safe mode, I uninstalled Malwarebyte. Then Win then loaded normally. Appreciate anyone's guidance and help.