Hello all. I am in the process of wanting to sell my mid 2009 MBP but I need some help/advice on restoring the HD so it's all wiped & ready for the next user etc. The problem I have, which I've just begun to realise when wanting to sell the MBP, is that I bought it second hand from eBay with mountain lion installed (purchased by the previous owner) & it didn't come with the original installation discs (which I presume should be snow leopard?). After looking further into how to restore my HD, it looks like I'll need one or the other? I'm new to macs / computers in general (I usually use mobile devices, iPhone, iPad etc) & didn't realise at the time of purchase that I'd need discs etc to restore it. Could someone please tell me my options that can fix this, I also have an apple I.D myself so I can purchase OS if needed? Also, I have the guys email still, as it appears when I have tried to update the installed Apple apps. I doubt I could message him after a year has passed & ask for his apple I.D to restore mountain lion :-D Any help would be greatly appreciated, thank you. Robert Edit* I searched the box & there were 2 discs in the little packet. One is '13 inch MacBook Pro Mac OS X Install DVD' (grey in colour) The other is '13 inch MacBook Pro applications install DVD'. The Mac OS version is 10.5.7. Do I just do a reinstall & delete of my HD now with the Mac OS X install DVD? & then do the applications DVD after? Will this clear the HD & return it back to original factory settings/OS X?