My hard drive went out on my mid 2009 MacBook Pro. I replaced it with a western digital Scorpio blue and when I go to partition it it says cannot allocate memory. It does this same message if I try and erase it. I am using the only disk I have though the snow leopard 10.6. Is it not partitioning because I must have the correct disk that came with the computer in instead of a later snow leopard? If so can someone help me out what exact disk I need and where to get them. Any help is greatly appreciated! Thanks