So, my dad can't find his macbook pro disks. He bought his macbook pro back in 2009 (i believe the spring) and I just bought mine in September. He needs me to reformat it for him, but like I said, he doesn't have his disks. He lost them. Can I use mine? I went through the beginning of the process.. I got to disk utilities and I was getting ready to "Erase", because I figured if it would let me get this far, then that means that the disk would work, however, I am afraid that once I erase, I won't be able to install. What if the disk doesn't work?? I am just curious if anyone else has had this issue or have used their disks on others computers that are different sizes. His has the same operating system and everything. It is just 10.5 and mine is 10.6. but I updated mine since I got it anyway. and so has he. I know his didn't come with it. idk. I don't really know that much about computers, as you can tell. ANY help that you can give me will be helpful. If we have to, we will pay apple and buy the disks again, but he doesn't want to do that. He is kinda sorta cheap it that way... heh. Thanks in advance!!