"The laptop died in the middle of writing an email. When I remove the hard drive and connect it to another laptop as an external drive (using a USB to SATA adapter) the drive shows up, but it shows as a 'Healthy (GPT Protective Partition)' with no drive letter associated with it, so I cannot copy files to another PC. When I try to talk to HP about the problem, they say that they do not help with backups. When I try to tell them I don't need help with the backup, but with what I need to do so I can see the data, they keep saying they do not help with backups.
Does anyone know how I can correct the partition information without losing all of the data on the drive?" – from RLKnecht at HP Support Forums
The user said that after he removed the hard drive from dead laptop and connected it to another computer, the drive was indeed recognized by and shown in computer. However, what really bothers him is that, the hard drive is now stated as a GPT protective partition; and what’s more, he loses entry to data saved there. After trying to seek help from HP support team, he still failed. Discovering this, we decide to offer solutions to recovering data off GPT protected partition and then deleting the GPT drive if needed.
Are you one of those users who accidentally meet OS (operating system) crash and want to access data in the hard drive and make it work again? Don’t be sad if you’re right now stuck with it. Here, we’ll analyze why you met such situation and how you’re able to get rid of it on your own.
About GPT Protective Partition
Most users’ natural response when they see this term will be asking the following things: what is GPT protective partition, how does it form and how to repair it and get data off. In order to make it clear to users, we have to mention something about GPT.
What Is GPT
Short for GUID Partition Table, GPT is a standard for the layout of the partition table on a physical hard disk, using GUID (Globally Unique Identifiers). It is a famous and advanced partitioning scheme used more and more frequently nowadays. Allocating 64 bits for logical block addresses, GPT supports a maximum disk size of 264 sectors. For disks which are made up of 512-byte sectors, the maximum size can be up to 9.4 ZB or 8 ZiB.
The most important reason why GPT appears is to replace the old MBR (Master Boot Record). For those disks which have a sector size of 512 bytes, MBR partition table does not allow the partition capacity to be greater than 2.2TB. After noticing this limitation, some hardware manufacturers, such as Seagate and Western Digital, start to upgrade the sector size of their large-capacity disks to 4KB.
This means that the effective size limit of MBR disks is temporarily raised to 8.8TB. This solution seems to work well, reducing users’ demand for GDP temporarily. However, it brings confusion as well: when booting from BIOS on a device with large block, how can we divide the disk partitions in the best way.
Apple once warned – we should not assume that all device block size is 512 bytes. The truth is some modern storage devices, such as SSD (Solid State Drive), might use 1024-byte blocks. What’s more, some MO (magneto-optical) discs might use 2048-byte sectors though they’re often not partitioned. With this in mind, some manufacturers plan to produce hard drives with 4096-byte sectors; but as of early 2010, this new kind of hard disk is still disguised as disk with 512-byte sectors in operating system with the help of firmware.
Why Choose GPT over MBR
In addition to the 2TB capacity limit, MBR disk has many other restrictions, thus an increasing number of users decide to replace their MBR disk with GPT/convert it to GPT. Here, we’d like to show users the reasons for choosing GPT over MBR:
GPT uses only LBA, so the CHS related problems would no longer exist.
Assuming the size of disk pointer and that of sector are respectively 64 and 512 bytes, we can find the largest disk capacity that GPT can handle with is up to 512x264 bytes.
Data structures are stored on 2 different parts of GPT disk: in the beginning and at the end. Such duplication increases the chances of successful recovery when damage is caused.
Cyclic redundancy check value of GPT disk is calculated for critical data structures to improve the chance of data corruption detection rate.
GPT stores all partition in a single partition table (with backup), so the extended partition or logical partition is no longer necessary. By default, GPT can support up to 128 partitions.
GPT uses a 16-byte GUID value to identify the partition type while MBR provides 1 byte partition type code; this makes partition types less likely to conflict.
As a result, you can choose to convert your MBR disk to GPT disk according to needs.
Tips: we don’t suggest users to convert a MBR disk with operating system to GPT because it may cause boot failure due to the different boot modes.
When Will GPT Protective Partition Appear
As a new kind of disk type, GPT is supported by most operating systems like Windows 7, Windows 8 and Windows Server 2003 SP1, Windows Server 2008. However, we find that the 32-bit Windows XP and Windows Server 2003 give no support to GPT disk. That is to say, when users connect a GPT format disk to a 32-bit Windows XP or 32-bit Windows Server 2003 computer, this disk will not be shown in Windows Explorer.
However, as the user said in the beginning of the article, the GPT disk does show up in Windows Disk Management (WDM) as Healthy (GPT Protective Partition) with no drive letter. That explains why it can’t be found in Windows Explorer. And the most serious problem is even when we right click on the GPT protected partition, the system will not allow us to assign a letter to it.
Yet, you need to know that GPT disk is supported (GPT protective partition will not appear) on all computers, including Windows XP Professional and Windows Server 2003, as long as they’re provided with 64-bit operating systems.
As a result, 64-bit operating systems offer better compatibility than 32-bit operating systems, so they all give both read and write support to GPT disk.
Now, the problem is – users who’re suffering from above situation needs to get back their important data saved on GPT protective partition and make it usable again. So, we change our topic to GPT protective partition data recovery and how to remove/delete/format GPT partition.
Clear GPT Protective Partition & Convert GPT to MBR
Imagine this: when your OS is corrupted, you take out the hard drive carefully and connect it to the other computer properly, only to find this GPT disk has become GPT protected partition. How would you feel?
We are pretty sure that you’ll be pissed off especially when there’re valuable files you need on that disk. You must be eager to find a way to carry out GPT partition recovery. Even if you don’t care much about the data on that GPT protective partition in XP, you definitely need a solution to make that disk available again. 2 approaches are provided in the subsequent paragraphs.
Using DiskPart Command
When you select the GPT protected partition, you’ll find the built-in Disk Management (DM) tool doesn’t offer a function like delete partition and format partition. So, you need to adopt another Windows snap-in tool called DiskPart.
Firstly, you need to open Diskpart.exe by following ways:
Click on "Start" button from the lower left corner of screen -> choose "Run" from pop-up menu -> input "diskpart" -> click on "OK" button.
Click on "Start" button -> select "Run" option -> input "command" -> click on "OK" button -> input "diskpart" -> press "Enter" in keyboard.
Secondly, you should enter a few commands to clear GPT partition:
Input "list disk" and press "Enter". After that, all the disks connected to this computer will be listed in order.
Input "select disk *" and press "Enter". "*" stands for the number of disk that you want to remove GPT protective partition from. You may confirm the target GPT disk by looking at the "Size" and "Free" information here or just opening DM to check. After that, a prompt message will show up – "Disk * is now the selected disk".
Input "clean". When the clean process is completed, you’ll see "DiskPart succeeded in cleaning the disk" prompt.
After that, you could just click on the button or input "exit" and press "Enter" to close DiskPart.
Thirdly, you could go to DM to check the result – whether the GPT protective partition in XP is gone.
Now, you can see that disk 3 has been changed from "Basic" and "Healthy (GPT Protective Partition)" to "Unknown, Not Initialized" and "Unallocated". That is to say, the work to delete GPT partition is finished.
Finally, you may reply on following methods to finish disk conversion from GPT to MBR:
Open DM -> right click on the disk -> choose "Initialize Disk". After that, you can right click on "Unallocated" space and choose "New Partition" to create partition(s) on it.
Enter "list disk" -> enter "select disk *" -> enter "clean" -> enter "convert mbr". However, you may failed sometimes by using this method. You may see "The disk you specified cannot be converted to MBR. Please select an empty GPT disk to convert." prompt message. So we offer an easier and more effective way in the following part.
So, it’s not difficult to see that DOS command still plays an important role in solving disk problems and it may never be replaced someway.
When you’re encountering above issue and not able to convert GPT to MBR, you should use MiniTool Partition Wizard instead (with which you don’t need to initialize disk first or know how to format the previous GPT partition).
Just open this software after you have removed GPT partition -> select/right click on the unallocated space on the previous GPT disk -> choose "Create Partition" or "Create" to build new drive on the disk so as to make it usable again -> press "Apply" and choose "Yes" to end.
You may plan to convert GPT to MBR to work this out; you may want to know how to format GPT partition; either way, you’ll lose all data. So, that’s why we’re feeling like offering a step-by-step tutorial on GPT protective partition data recovery.
Please don’t hesitate since your needed data could disappear in a flash, leaving no room for regretting. The sooner you take measures to recover hard drive data, the higher the successful rate will be.
Whether you're suffered from data loss now, we recommend that all of you to install MiniTool Power Data Recovery to computer because it is a piece of powerful data recovery software that could help you get out of annoying data loss issues efficiently.
Here are the 3 steps for you to complete GPT protective partition data recovery:
Step 1: open MiniTool data recovery software and choose "Damaged Partition Recovery" from main window.
Step 2: select the GPT disk with protective partition and click on "Full Scan". (You can set the software to scan only needed types of files under "Settings").
Step 3: look through the found files and pick out your needed ones to save by pressing "Save" button.
MiniTool Power Data Recovery gives support to both GPT disk and MBR disk. So you can also use it to recover MBR disk data no matter how they are lost – accidental deletion/formatting or other reasons.