I am running a 2009 macbook pro. I installed os x mountain lion on it a few months ago. Last week it crashed and now will only but to the recovery 10.8 drive. While there I am taken to the OS X Utilities menu. I have been trying to reinstall mountain lion via the Reinstall OS X option but I keep getting an error saying "An error occured while preparing the installation. Try running this application again." I do not have the original disc that came with the computer. How can I fix this?