Missing Partition

kadafi

Member
Nov 1, 2006
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0
61
So I'm on here because I'm helping my friend with his Computer.

He recent bought a SSD (Crucial BX100) and I installed Windows 7 on there. So basically the problem we're having is one of the partitions from his 4TB drive doesn't show up when booting into Windows on the SSD and I'm not sure why. He has windows setup on one of the partitions of the 4TB drive. When booting from the partition that has windows on it everything shows up correctly.

Note that i had to split the 4TB drive into 2 partitions as windows wouldn't recognize it as a 4TB. So I used Seagates Diskwizard to split it into two 2TB partitions.

If it was my HDD I would just reformat it but knowing my friend he probably wont do that unless there's no other choice.

So yeah I'm out of ideas on what the problem could be. I don't have the computer with me but if you guys have any ideas let me know and I'll have him check or try it.

Specs.

Windows 7 Ult
i7 2600 Sandy Bridge
AsRock Z77 Extreme 4
8GB G.Skill PC12800
EVGA 950
 

Burpo

Diamond Member
Sep 10, 2013
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Disk Wizard is interpreting the larger drive via an overlay, also known as using a Dynamic Drive Overlay. Unless you boot to the drive with the overlay, the 2nd partition will not be seen. You can alternatively boot using a rescue disk made with Disk Wizard that provides the Dynamic Drive Overlay, and the partition will be seen. The problem is the bios can't see/boot the full 4Tb drive without the overlay unless you partition it as GPT (using UEFI bios) instead of MBR. Your motherboard does support UEFI and GPT partitioning, but unless you did so originally, the overlay is what enables the larger size hard drive to be partitioned with an MBR boot sector. A 64 bit operating system is also required to see/boot larger than 2Tb drives.
Here's a Tutorial.
http://www.tomshardware.com/faq/id-1923415/install-windows-3tb-4tb-larger-hdd.html
 
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kadafi

Member
Nov 1, 2006
27
0
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Thank you for your response.

Since the 4Tb drive is no longer the main drive since he now has a SDD with windows on it (The SSD is what he wants to boot from), the only way for the 4TB to show up is to basically reformat it to GPT?
 

Burpo

Diamond Member
Sep 10, 2013
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You can try using Disk Wizard to partition the SSD, then install Windows to it. As long as the overlay is on the boot drive, it should then see the partitions on the 4Tb drive. Or you can try Mini-Tool (free download) to see if it will put the overlay on the SSD. The drive overlay needs to be loaded during boot to see any other partitions created by Disk Wizard.

http://www.partitionwizard.com/free-partition-manager.html
 
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VirtualLarry

No Lifer
Aug 25, 2001
56,571
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I think that Burpo has correctly diagnosed the problem, it does sound like a missing disk overlay driver on the boot SSD.

Ideally, you would back up the data to another (4TB?) drive, and then erase and re-partition the drive using GPT (requires 64-bit Windows), as a single 4TB GPT volume, which then will be able to be used with any OS that supports GPT volumes.

DDOs (dynamic disk overlays) have always been a bit of a half-assed solution, and are generally to be avoided if one can help it.
 

Burpo

Diamond Member
Sep 10, 2013
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Yeah, there is inherent latency when using an overlay, but it's the lesser of 2 evils in this situation. Otherwise, like you said, he'd have to rebuild the 4Tb drive.
 

kadafi

Member
Nov 1, 2006
27
0
61
Thanks for the replies guys! It helped a lot. I will let my friend know this is what needs to be done.
 

silicon

Senior member
Nov 27, 2004
886
1
81
Thank you for your response.

Since the 4Tb drive is no longer the main drive since he now has a SDD with windows on it (The SSD is what he wants to boot from), the only way for the 4TB to show up is to basically reformat it to GPT?

i needed to do this with a new 3TB seagate drive. Using MBR only 2 thirds of the drive was usable but changing to GPT allowed me to format the drive into a single partition.