Help Needed: recover lost partition

How to use TestDisk to recover lost partition
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Posts: 2
Joined: 04 Jan 2016, 00:44

Help Needed: recover lost partition

#1 Post by bluebottle66 »

Hi, I have a desktop which I installed two systems: Windows Vista and Ubunto (boot managed by ubunto)
. In Windows it has 3 partitions: 400G for system, and 2 800G for storing.
Last couple days, the windows system start to crash, extremely slow, and
pretty much not usable. so I tried to reinstall a Windows 7 ... however
installation disk keep complain about the partition and cannot install to
it. (even it finds all the 3 partitions just fine, but just cannot install to it)

I searched online and someone suggest to use DISKPART (during
installation) to select that disk, then do clean, convert mbr, create
partition primary, active and format quick fs=ntfs. So, I select that 400G disk and did it...

Now seems i totally lost the other two
partitions, and they combined to a 2TB disk. W7 installation disk still
cannot install to it.I am afraid i lost all my files in the 2 800GB

Any suggestions? can I still recover the two disks and the files? I am running TestDisk now
in Ubuntu for deeper dive on the now 2TB NTFS drive and will see whether it can find anything.
Also why W7 installation disk keep cannot install to those partitions?
thanks a lot for any help or suggestion you can provide here!

Posts: 4
Joined: 02 Jan 2016, 23:51

Re: Help Needed: recover lost partition

#2 Post by Alien »

I immediately got worried when I read "clean". From the manual, you can read about the command: ... s.10).aspx
Removes any and all partition or volume formatting from the disk with focus. On master boot record (MBR) disks, only the MBR partitioning information and hidden sector information are overwritten. On GUID partition table (GPT) disks, the GPT partitioning information, including the Protective MBR, is overwritten; there is no hidden sector information.

So the posting you found did help you to install on that disk, but only by actually removing all partitions. Luckily it said "format quick"..

Did you try running TestDisk and doing a full analyse on the disk? It might locate the lost partitions and could help you in regaining access to your data.

Posts: 2
Joined: 04 Jan 2016, 00:44

Re: Help Needed: recover lost partition

#3 Post by bluebottle66 »

Thanks, I ran testdisk for a deep analysis and it successfully found the two missing partition. I now recovered the important files to Linux hard drive. Thanks God.

Now I tried to install Windows to that 2T hard drive. During installation, I partitioned it to three pieces (400GB, 800GB, 800GB) In diskpart, I select first volume and make it active, it shows the first partition is System and the other two are Primary, all three are NTFS. However Windows installation keep saying "setup was unable to create a new system partition or locate an existing system partition"

I played around a bit but it keeps giving me the same error. (eg. do not partition, just try to install to that 2T drive)

Anyone can help to figure out the issue? FYI, since I had two OS before on two different hard drive, the booting part is managed by GRUB from Linux disk. Not sure whether that is causing issues.


Posts: 4
Joined: 02 Jan 2016, 23:51

Re: Help Needed: recover lost partition

#4 Post by Alien »


Well I think I know why Windows is complaining. I don't know why _exactly_ [you can Google it if you want], but when you install Windows 7 on a disk it does so in two partitions, not one. Since you only have one, it fails to install.
Try this:
Remove that 400GB partition. Either via Linux create two partitions, or try it inside Windows-installer:

During Windows Installation --> Shift F10:

list disk // You will see amount free which you need later on.
select disk 0 // Or whatever the correct number is.
create partition primary size=<total MB free - 128> // If you don't know total free, you can "create" a partition inside Windows-installer which will default at max size, just don't press the "save" button :).
create partition primary size=128 // Note that if it says you only have 127MB free, remove previous parition and recreate it with 1MB less.
list partition // Note your two new partitions.
select partition 1 // Change the number to match your new big partition.
format fs=ntfs quick unit=64k // I recommend 64k cluster size for performance reasons, 4k is default and works fine too.
assign letter=c
select partition 2 // Change the number to match your new small partition.
format fs=ntfs quick unit=4k
list partition // Optional, but nice to see the end result?