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I can't install Mountain lion. It says my HD is locked

I am having problems installing mountain lion on my MacBook Pro. I downloaded the software and restarted my computer. It takes me to the install screen and I click through and agree to the terms and conditions. it asked me to select where I want to install Mountain lion and I try to click on my Macintosh HD and it says it is locked. I tried to bring it back to lion, but it did the same thing. It just says that my hard drive is locked or can't find it. Please help me figure out what to do.

MacBook Pro, OS X Mountain Lion

Posted on Jul 25, 2012 7:28 PM

Top-ranking reply

Helen Webb1

Level 1

5 points

Posted on Jul 27, 2012 4:30 AM

I'm having the same issue!

View in context

34 replies

Nov 3, 2015 11:48 AM in response to danielfromwhitman

I just encountered this issue with my old early 2011 MacBook Pro... The OS indicated the drive was fine upon ' verify disk.' But, it would not boot anymore.... Then, I got into the boot with command + r option to repair the OS. Upon trying to reinstall OS X Mountain Lion got the ' disk locked' message. This told me somehow the MBR ( master boot record / equiv) was messed up; possibly bad instructions, or even more likely, hard drive going south.

So, I took someone's advice in this thread, I pulled the drive out of the laptop, hooked it up to an enclosure, connected it to my new MacBook Pro, and the OS X Yosemite tells me immediately, ' bad hard drive, cannot fix, will run, but may die soon. Back up ASAP.' So, I'm now backing up...

Thanks to this thread you all saved me a lot of time by trying to reinstall the OS, tinkering with settings and different boot modes... Instead of going any further with all that, I just yanked the drive and hooked it up to an enclosure and I'm getting my lost files back!!!! I"M HAPPY 🙂 🙂 🙂 🙂 🙂 ( and I know where to go from here...!)

THANKS!

Feb 4, 2016 6:08 PM in response to hoopty-doo

I ran into this problem because I had no drives mounted. Go into utilities, disk utilities and check to ensure you have the drive/partition mounted that you want to use for the OS install.

chituh

Level 1

4 points

Sep 18, 2016 5:37 AM in response to danielfromwhitman

having the same problem

Eric Root

Level 10

684,681 points

Sep 18, 2016 8:19 AM in response to chituh

You might want to consider starting a new discussion. Since this one is a couple of years old, less people are likely to look at it. A new post would be much more visible. You can link to this one.

I can't install Mountain lion. It says my HD is locked