Hi gurus, I just got myself a crucial M4 and replaced the default HDD. my steps are: - format the SSD externally using usb 1st, erase and format 1 partition in journal extended. - Prepared my mountain lion thumbdrive using the correct step (it works on my other mac) - replaced the default HDD with my new SSD. - Boot OS with option key holding. - only my mountain lion flash drive appear. So i selected. - it straight away give me a "no entry sign", not even an apple logo. May i know what went wrong?