Sata HDD works in external dock but not internally?

Megahertz07 · 31 Aug 2016

Jumanji, for me you're "the" disk guru, but in this case I will disagree with you.
DNYBOY has a marvelous UEFI MB and has installed Win 7 as legacy. If he had installed as UEFI, he wouldn't be having problems with GPT disks.
With legacy bios you can only have disk access up to 2.19 T. To have access to larger disks you make other partitions and link them to show as one. That is why drive F: has two partitions.

From Seagate Support for Disk Drives Beyond 2.2 TeraBytes (TB) and 4K Advanced Format Sectors
Windows operating systems that boot from an MBR are therefore limited to 2.2TB per MBR. A 3TB disk drive in a legacy BIOS and Window system will need a DiscWizard device driver to access the full capacity of a 3TB disk drive. Two partitions will be necessary because of the MBR limitation. The device driver mounts the capacity above 2.2TB with another MBR which looks to the system as a second virtual “physical” device.

Edit: If someone don't agree, PLEASE post. I'm here at this forum more to learn, not to teach.

DavidE · 31 Aug 2016

@DNYBOY said these drives work perfectly in other computers.
It would be interesting to know if the other computers are UEFI or Legacy Bios.

Also, the 2TB drive should have full capacity available if it is initialized as MBR, no need for GPT on this data drive.

jumanji · 31 Aug 2016

I had added a last line to my previous post DavidE has also stated that he has a legacy + MBR install and he has no problem

jumanji · 31 Aug 2016

I had to break my previous post due to other exigencies.

@Megahertz07, advanced formatting has nothing to do with GPT or MBR partition structure.

From your own reference Support for Disk Drives Beyond 2.2 TeraBytes (TB) and 4K Advanced Format Sectors

"GUID Partition Tables (GPT) can define drives larger than 2.2TB. You can use GPT today on any Windows 10/ 8.1/8/7 and Vista system as a non-booting data drive. Windows can only boot a GPT partition on a new type of BIOS called UEFI."

"Windows 10/8/8.1/7 and Vista can mount a GPT non-booting data drive"

If your boot drive is less than 2TB, you can install windows with Legacy+ MBR. Windows will still read >2TB data drives which necessarily have to be GPT to have full capacity access. Whether a particular drive has the normal 512bytes/sector or advance formatted 4096 bytes/sector, the drive controller in the HDD will notify the OS and the OS will read the drive accordingly. This has nothing to do with the UEFI/Legacy BIOS.

Only on Operating systems ( such as XP) that do not have the capability to see GPT structure/ read the advance formatted drives (4096 bytes/sector size) you need an interface like the Disk Wizard in case of internal drives >2TB and a special drive Translation circuitry in the SATA to usb bridge in external drives >2TB

That is how I understand it.

DavidE · 31 Aug 2016

The 3rd screen print (Partition Wizard) in post #14 lists 6 drives with an EFI partition and 2 other partitions, all the same size.
How is this possible, what is PW seeing ?
If the PC's the HD works on are UEFI, and this drive was initialized there, could that cause this ?
I think we need to see screen prints with the 4TB drive attached to a PC where it works.

I would disconnect the 2TB drive and just work on troubleshooting the 4TB drive to simplify testing.
I'm guessing the 4TB drive is somehow causing these 6 drives, but that's just a guess.

jumanji · 31 Aug 2016

OP's first post first screenshot shows three media drives each 21.8TB. OP says "Those huge media drives are connected to the above Fibre Channel Adapter and connect at startup through a program called metaSAN (this is a work PC). Ive tried disconnecting this connection and disabling this program from running at startup but there is still no change in gaining access to these WD HDDs, even if I boot into safe mode." - his post #5.

Layback Bear · 31 Aug 2016

Just a thought that may or may not have been covered.

On troubled drive
Right tick and select Property and select Security.

Verify that Systems and Administrator has full control.

I'm back to watching.

DNYBOY · 31 Aug 2016

DavidE said:

Have you tried initializing the drive as GPT while it is connected to the motherboard (not in the dock) ?
You might also want to do a Diskpart Clean while it is connected to the motherboard (before initializing).

Hi David, thanks for your thought's but when I have either of these drives connected internally I cannot do anything with them including read/write/format/partition. I have managed to use the "clean" function on them but it has not helped. After the clean function I have to connect them externally to partition and format them but I still have the same issue reading them once they are internal again.

Megahertz07 said:

DNYBOY has a marvelous UEFI MB and has installed Win 7 as legacy. If he had installed as UEFI, he wouldn't be having problems with GPT disks.

Just a question, If this were true it would only effects GPT disks? I have formatted these disks to MBR and I still cannot access them.

Layback Bear said:

Just a thought that may or may not have been covered.
On troubled drive
Right tick and select Property and select Security.
Verify that Systems and Administrator has full control.
I'm back to watching.

I cannot do this whilst connected internally (access denied errors) but I have done this whilst drives are in the external dock but once again no joy as soon as they back inside the PC.

As for the 4TB limitation is not an issue here Windows can see the whole disk, the limitation is directly linked to the external dock I'm using.
My next step is to go and buy a small 500GB drive brand new drive and see if it can be used in this PC, if it cannot I don't know what else to try other than stripping it all back and re-installing which I really wanted to avoid

DavidE · 31 Aug 2016

Can you post screen prints of Disk Management and Partition Wizard with the 4TB disk attached to a PC where it works perfectly ?
On a PC where it works perfectly, is that PC Legacy Bios or UEFI ?
What type of motherboard is on a PC where the drive works ?

You have also posted about formatting, but you never mentioned INITIALIZING.
In my experience a drive needs to be initialized, maybe you are doing things differently than what i understand and do.
Was the 4TB drive initialized on a working PC before ?

You can try another disk, if you do i would try something other than WD and see if that makes a difference.
To me it seems the 2TB drive should work if it is initialized as MBR, you don't need GPT for that drive.

Do the "working PCs" have other drives > 2TB, and if so, what manufacturer of drive ?

jumanji · 31 Aug 2016

While you process what DavidE has asked you to do in the previous post, I shall just butt in to say that there is no need to go and get a new HDD just to ascertain whether the new HDD works well in your system.

We can always bring your existing 2TB and 4TB HDDs to "just out-of-factory condition" - a clean drive