I have a mac book 2009 . I used disk utilities to reinstall my os and did not do it correctly. Now when I start my mac, it starts the disk utility and will not do anything else. It says the hard drive I try to install on is locked.
I have decided I would like to put in a ssd hard drive. I don't know how to install my os Mountain Lion, on it.I bought it in the store.
MacBook, OS X Yosemite (10.10.2)