So I have a 3TB HDD and since I have got it, it has always shown 2TB. I assumed I got the wrong hdd, however looking in disc manager, I do not, there is 746.52gb unallocated, I cannot allocate it, so I looked it up, I have to make the drive GPT instead of MBR, but I already have almost 2TB of stuff on there that cannot lose access to, and I need to be able to allocate that other 1tb I cant access. Is there a way to convert the HDD from MBR to GPT without data loss? I might have to find multiple hard drives from old laptops to temporarily store data but I really do not want to do that, any ideas?
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Convert HDD Partition Type Without Data Loss
Home » Forums » AskWoody support » PC hardware » Questions – Maintenance and backups » Convert HDD Partition Type Without Data Loss
- This topic has 9 replies, 9 voices, and was last updated 5 years, 10 months ago.
Viewing 6 reply threadsAuthorReplies-
RetiredGeek
AskWoody_MVPJuly 2, 2019 at 5:42 am #1865187Martin,
I’ve used EaseUS Partition Master Free to do this several times w/o issue.
Of course, it’s still a very good idea to have a backup JIC! YMMV.
HTH
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This reply was modified 5 years, 10 months ago by
RetiredGeek.
1 user thanked author for this post.
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This reply was modified 5 years, 10 months ago by
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GoneToPlaid
AskWoody LoungerJuly 2, 2019 at 10:14 pm #1866128Yeah, it works. I am not too keen about the telemetry in EaseUS products. Nothing nefarious. I have to admit that EaseUS Partition Master is straightforward to use, and that it has been bulletproof for me as well. Run it only after having run a Scandisk and confirming that there are no errors on the hard drive’s partition(s). If you are paranoid about telemetry, simply uninstall it after using it. It does uninstall cleanly.
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mngerhold
AskWoody LoungerJuly 2, 2019 at 5:50 am #1865195stuff on there that cannot lose access to
I would say the first thing you should do is purchase a backup external drive – I know RG mentioned backup, but do that first! You may prefer to trust the cloud (I wouldn’t).
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anonymous
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jabeattyauditor
AskWoody LoungerJuly 2, 2019 at 10:11 am #1865454Windows 10 has a native conversion tool now – mbr2gpt. You can only run it from the recovery environment or install media though.
Looks like you can now run it from the running OS (1703 or higher) natively using the /allowFullOS option.
There’s a long list of caveats at the site noted in cmptrgy’s post.
1 user thanked author for this post.
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cmptrgy
AskWoody LoungerJuly 2, 2019 at 10:03 am #1865453Windows 10 has a native conversion tool now – mbr2gpt. You can only run it from the recovery environment or install media though.
MBR2GPT.EXE
https://docs.microsoft.com/en-us/windows/deployment/mbr-to-gpt
MBR2GPT.EXE converts a disk from the Master Boot Record (MBR) to the GUID Partition Table (GPT) partition style without modifying or deleting data on the disk.HP EliteBook 8540w laptop Windows 10 Pro (x64)
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cmptrgy
AskWoody LoungerJuly 2, 2019 at 8:39 pm #1866076Windows 10 has a native conversion tool now – mbr2gpt. You can only run it from the recovery environment or install media though.
Looks like you can now run it from the running OS (1703 or higher) natively using the /allowFullOS option.
There’s a long list of caveats at the site noted in cmptrgy’s post.
Actually now that I’ve had time to compare them I like RetiredGeek’s recommendation in post #1865187
HP EliteBook 8540w laptop Windows 10 Pro (x64)
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Alex5723
AskWoody Plus -
rc primak
AskWoody_MVPJuly 8, 2019 at 4:37 am #1871430Also useful and successful for me is Minitool Partition Wizard:
Windows 10 does indeed have in its Disk Management or DiskPart tools the ability to make this conversion.
As posted above, these methods do carry some risk. I would make a backup first, but then again I have like a million spare hard drives lying around my place.
-- rc primak
1 user thanked author for this post.
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