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Windows 7: Windows 7, GPT and Unknown file system

09 Aug 2013   #1

Windows 7 Ultimate x64
Windows 7, GPT and Unknown file system

I have a really big problem .

In the beggining of the year, i had 2 hard drives.

Then i bought a Western Digital 1TB hard-disk a while ago and installed it on Windows 8 64bits.

I put all my data from long time ago in it and used it for about 5 months.

It was all fine 10 hours ago when I decided to install Windows 7 64bits (in place of Windows Eight). I formated one hard disk entirely (didn't mess anything with the others) and successfully installed Windows 7.

After the process was done I started Windows 7. The problem is that I noticed that Windows 7 doesn't seem to be able to deal with my WD 1Tb Hard Disk .Windows 7 can see it in Disk Management but doesn't even recognize the Free Space and the Used Space (should be 470gb used).

View image: 3

I can't even assign a letter to it, the only option I have is to Delete it. I tried many others software and they do the same, they partly recognize the 1TB hard drive, but doesn't seem to able to detect free-space and used space. They also seem not to be able to do anything with it but to able to delete it.The only thing they do is point out it's GPT.

Here are the Print Screens :
View image: 1

I'm pretty sure I didn't do anything wrong with this disk in the Windows 7 installation process, and I didn't format it and didn't try to do anything with it.

The data I have on it is really important and I can't afford to lose it. While all evidence points to the fact that the data is still there, I still have a lot of fear that the data is all gone.

I don't even know if the Data is still there and it's just a recognition problem, or if my data is all lost, or if i need to boot into this Hard-disk.

What should I do?

Thanks a lot

My System SpecsSystem Spec
09 Aug 2013   #2

Windows 10 Pro

Do you see the drive in my computer? can you run check disk on it? Are you able to boot into safe mode and see if you can access it this way? The drive may have failed. This is why its important to keep things backed up.
I would suggest trying out minitool partition wizard and see if that program can detect it. It may just need to be set as an active drive or be set as logical. I would try that software out, and see what you can do. Another alternative is to boot into a live linux cd and see if you can see your data. If you do not know how to do this, I can give you step by step. I would unplug the drive if your using your computer and not trying to get the data off. If the drive is failing, you do not want it connected to power otherwise the disk will fail quicker. Especially with sensitive date on it, your first task should be trying to get the data off the drive.
My System SpecsSystem Spec
10 Aug 2013   #3

Microsoft Community Contributor Award Recipient

Windows 7 64 Bit Home Premium SP1

Hello hnlive. Welcome to the forum.

There is a rule.
You can mix-and-match the disk systems of multiple hard drives in a PC (MBR and GPT), but the Boot Partition must be on the GPT drive.
"Systems that support UEFI require that boot partition must reside on a GPT disk. Other hard disks can be either MBR or GPT"
I'm guessing that Windows is ignoring the drive due to this rule violation.

You could attempt to convert the GPT drive to MBR, but there is always danger of losing data when doing this, so caution and backups are necessary.

You could find someone you know that has a system with Windows installed on a GPT disk, then connect your GPT drive to that system and backup your data.
Or you could convert your MBR drive that you installed W7 on to GPT (all the same warnings apply).

The problem will be further complicated if that GPT drive has an operating system still on it, or if any of it's partitions are marked Active.

So let us know what you did in the OS conversion in detail, every bit of info helps.
My System SpecsSystem Spec


 Windows 7, GPT and Unknown file system

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