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John T. F.
John T. F., Mac Druid
Category: Mac
Satisfied Customers: 3055
Experience:  20+ years in the computer/Mac industry
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hi I just tried to erase my macbook pro and then reinstal OS

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hi I just tried to erase my macbook pro and then reinstal OS but for some reason when I try to reinstal OS it's only shows one hd which is recovery hd and it says it's locked. can you help me with this issue?
Hello! My name isXXXXX will work diligently to provide accurate advice and information.

Can you tell me what version of OS X you are trying to re-install and how you initially erased the Macintosh HD volume?
Customer: replied 4 years ago.
Mountain lion and initially I went to command+r then du then I think I unmounted hd I think may be this is a problem
Thanks, Julia.

If you completely shut the Mac down, then restart, command+r, and go back into Disk Utility - can you tell me exactly what items are listed in the left hand sidebar?

Customer: replied 4 years ago.
Macintosh hd then SuperDrive then disk1 and then Mac OS X base system
Thanks, XXXXX XXXXX you try to verify Macintosh HD, does it report that it is OK?

Customer: replied 4 years ago.
Yes
Okay, good. When you select Macintosh HD, what does it show as the Format at the bottom of the window?
Customer: replied 4 years ago.
Name: Macintosh hd Type: logical volume group Disk status : online Capacity: 499.25 gb Available : 498.93gb used 318.8 mb that what I have on the bottom but if I select Partition then there it says format Mac OS Extendet ( journaled)
What is listed directly above "Macintosh HD" at the left, if anything?

Customer: replied 4 years ago.

Nothing

Customer: replied 4 years ago.

I had previously Macintosh HD and then second Macintosh Hd listed. First one had only two tubs, which are first aid and Partition, and second one had three first aid , eraise, partition. Now after eraising , second hd desapeared,


 

Okay, are you able to repartition the Macintosh HD volume?

In Disk Utility, choose your hard drive from the listing in the left sidebar and then choose the "Partition" tab.

Under Volume Scheme, click "Current" and choose "1 Partition".

Name your hard drive on the right side (usually "Macintosh HD") and choose "Mac OS Extended (Journaled)" as the format.

Now click Apply.

Once the process has completed, exit Disk Utility and attempt to install OS X.

John
Customer: replied 4 years ago.
It's all faded out and doesn't allow me do anything
Customer: replied 4 years ago.
It's says this partition a locked disk and can not be resized until it is unlocked
Hmmm, are you able to Erase it?
Customer: replied 4 years ago.
No there is no option for it
please go up to the "Utilities" menu at the very top of the screen and choose Terminal.

 

Type

 

diskutil CoreStorage list

 

and press enter

 

then tell me what it says.

Customer: replied 4 years ago.
On very top menu next to apple sign I have disk utility then file then edit then images window help non of those tubs have terminal
Okay, quit Disk Utility and go back to the previous screen and then look.
Customer: replied 4 years ago.
It says : core storage logical volume groups (1found) Then logical volume group DE0c3216-f732-49ef-a16b-fb0f0c671963. Then name Macintosh hd, size 499.2 free space 498.9 then physical volume a62b47cd-79a4-4d36-8fdc-7b367635aceb. Then index 0 disk disk0s2 status online size 499.2
Okay, I believe your screen looks similar to this:

graphic

Note the long string in the red box that is next to Logical Volume Group with the name Macintosh HD. This is called the UUID. It appears yours is as follows but verify that:
a62b47cd-79a4-4d36-8fdc-7b367635aceb

Next type

diskutil CoreStorage delete UUID

(where "UUID" is replaced with the string you identified)
and press enter/return.

Once the CoreStorage volume has been deleted, you should be able to return to Disk Utility and format the hard drive. You may or may not have to restart the system and return to the Recovery HD partition first (Command-R at startup).

In Disk Utility, select your normal, physical hard drive from the list in the sidebar and then choose the "Partition" tab.

Under Volume Scheme, click "Current" and choose "1 Partition".

Name your hard drive on the right side (usually "Macintosh HD") and choose "Mac OS Extended (Journaled)" as the format.

Click options and verify GUID partition table is selected and click OK.

Now click Apply.

Once the process has completed, exit Disk Utility.

Then, try installing OS X.

John
Customer: replied 4 years ago.
Thank you looks like It did allowed me to start installation for os but I ll see if it will work for me to the end . I ll talk to you later
You are very welcome!

If you continue to have issues on this topic, just reply back to this discussion. I will be more than happy to work with you further. Hopefully, this info will answer your question. If so please, please remember that when you are asked to give a rating, you are rating my personal service only and not this website itself or your issue.

Thanks and good luck,
John
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