Thanks, the OS is loading up now after remaking the package. However now I have another issue, but it might not be one you can fix. With a student user on the standard RM CC4 user policy the App Inventor website doesn't seem to recognise that the emulator is running, when you click to connect to the emulator it says please run the aistarter and try again, even though the emulator is already running. I have done some testing and have found that it is the policy that disables use of command prompt for standard student users. In you benefits section on the package download page you state that no command prompts are required, could I have done something wrong with the package or could it simply be that even though no command propt windows open the user still needs access to it?