Erasing all data from a Macbook late 2009
I want to sell my old Macbook white, and was following instructions to install the original disk holding the c key in order to then use the disk utility function to erase data. However, when I try to install the OS X from the disk, it says I cannot install that version. My Macbook has been updated to the most recent version of the operating system, but I thought it would still let me use the original disk. Any ideas?