I recently received a MacBook Pro from a friend that had no hard drive and he wasn't sure if it was working. I found a 320 gb drive from a laptop I had lying around so I decided to put that in and try get it running. When I turn it on it shows a blank white screen for about 30 seconds then the screen flashes black and it goes to a Windows Resume Loader screen (Windows was installed previously on the drive). I have tried to do the Command + Option + R thing at the start to get into recovery mode but it is not working. I am not sure if I am doing anything right with this because I am very new to Macs 😛