Why is 1 physical hard drive shown as 2 disks by disc management

[peter 555]

During a backup to a SATA hard drive power was lost and the disk corrupted.
I put the hard drive into a USB enclosure and I am trying to reformat.
Under disk management the hard drive is showing as 2 disks.
I have used discpart to clean and reinitialised as GPT using disk management
But I cannot get back to 1 disk.
For some reason I do not understand 1 physical hard drive in an external enclosure is being shown as 2 logical disks.
The only other storage connected is a small SSD with the operating system on. Windows 10.
There is definitely only 1 hard drive connected.
Somehow It is a 3 TB disk and I want to format it into a few partitions.
But before I can format I need disk management to show the 3 TB disk as 1 disk.
Discpart operates on logical discs and partitons.
But why does discpart show 1 physical hard drive as 2 discs.
How can I reset/reinitialise the hard drive so discpart and disk management only see 1 disk.
Thanks

 

[peter 555]

Further info.
1 physical disk present.
Disk management shows as 2 basic disks.
How do I delete the 2nd disk and get back to 1 basic disk.
Thanks.

 

[peter 555]

your PC has only one physical disk that has two partitions. in disk management, right click on the disk you want to delete and select delete volume. now there will be some space unallocated. to add this space to disk 1, right click on disk 1 and select extend volume. follow the on-screen instructions that come up next.

be sure to take a back up of the data that is present on "disk 2" or else you will lose everything.

 

[peter 555]

Thanks Gamerboy.
When I tried to add the space to disc 1 I got message saying that the selected basic discs would be converted to a dynamic disc.
I am wanting the 1 physical hard drive to be 1 basic disc.
Also when I tried that option the message "the operation is not supported by the object"
And still 2 basics disks are shown.
In the disc management lower panel it shows my operating system as disk 0
underneath it shows 75% of the physical hard drive as basic disk 1
underneath that it shows the remainder of the hard drive space as basic disk 2
normally each physical hard drive is shown in full with its partitions on 1 row of the display
but somehow the hard drive has been split into 2 basic disks.
Thanks

 

[Colif]

Can you show us a screen shot so we can stop guessing??

what does the bios see?

http://www.eightforums.com/general-support/45874-how-merge-2-partitions-disk-0-disk-1-one-hdd-2.html

 

[peter 555]

I am new to this forum.
Unfortunately I have posted this question in the wrong category by mistake.
Should be in 'storage'.
I have been reading through the help info on how to post and use this forum.
On posting images the help info says 'check out our guide on posting images' but I cannot find this guide.
I do not know how to attach images or screenshots.

Thanks Colif for the link. It looks like the answer in that link is that were 2 physical hard drives.
I have just 1 hard drive.
Definitely only 1 as in an 1 hard disk sized external enclosure.
I have never owned either a 2TB or a 750 GB hard drive but this is what is being shown.

Update on where I am :-
Yesterday I installed 1 Toshiba 3GB physical hard drive in an external enclosure.
It is being shown as two completely different physical hard drives.
As if there were two drives in a 1 hard drive sized enclosure.

The BIOS shows
USB storage devices
Toshiba HDWD130 0200
Toshiba HDWD130 LUNI0200

Device manager shows
Toshiba HDWD130 LUNI USB device
Toshiba HDWD130 USB device

Disc management is showing
Disk 2 basic 2018 GB
Disk 3 basic 746.52 GB

Disk 0 is SSD with operating system
Disk 1 is internal hard drive

Disk Management is showing the Toshiba split over two separate rows.
As opposed to how the hard drive was shown previously when an internal hard drive on SATA connection.
Which was as a single row with 5 partitions.

As the hard drive has been split into a 2TB part and 750 GB in 2nd disk it looks like the hard drive is being treated as set up with MBR.
It is definitely setup for GPT.
I used discpart to clean and then disk management to reinitialise as GPT.
I did this again to be sure.

Both disks are available for use and I can write to both disks.
If I try to eject, both are shown on same USB, and both ejected together.
When ejected both disappear from disk management.

This effect has occurred since a backup to the hard drive was interrupted by a loss of power.
Some unusual reformatting seems to have taken place.
I will look into what software debug tools the manufacturer has.
I will check out low level formatting which I am new to and never used before.

 

[Colif]

Toshiba HDWD130 0200 = http://hdd.userbenchmark.com/Toshiba-P300-3TB/Rating/3591
Toshiba HDWD130 LUNI0200 is slightly rarer, can only find one reference to it and its in Russian, seems to be a review for same drive so that doesn't help

Curious what HDTune trial sees the drive as: http://www.hdtune.com/

its odd that a 3tb drive appears as two different drives in the bios. Have you deleted all the partitions on both drives?

it does seem to have something to do with mbr still as its similar to this: http://www.tomshardware.com/forum/298696-32-shows-746gb
https://www.partitionwizard.com/partitionmanager/3tb-drive-shows-746gb.html

plenty of cases of 3tb drives being seen as 746gb but not exactly the same as yours as you can see both partition tables.

 

[Colif]

It's quite possible that it's the USB controller inside the drive that's presenting two devices to the host rather than software loaded into Windows itself. If so, I have no idea how you'd deal with that. I guess you'll just have to try the instructions in the e-mail to see what happens.

there be an angle we had no approached??

http://www.tomshardware.com/forum/274015-32-external-usb3-drive-shows-devices

it sounds like its the enclosure presenting the hdd to PC as two devices. Have you tried to format drive attached internally?

note: to attach screen shots, share them on a site like imgur and post the link. IT doesn't mattyer which forum you post in, if its got the right links enough people will see it

I know what gpt is, I knew it had to be formatted in that for pc to see more than 2,2tb. it doesn't appear to be a formatting issue and more a hardware in enclosure issue.

 

[peter 555]

Thanks for the replies.
I am busy at work so will be some gaps in my replies.
I will install internally on a SATA port and see how it shows up.
The Toshiba is usable and 3TB are available.
I am storing data on both discs.
They are both accessible by windows.
It is like having 2 partitions.
But just that they appear as 2 discs in device manager and on diffrent rows when viewed in Disk Management.
Thanks

 

[adamgoff1]

When this happened to me it turned out the disk had been divided into 2 Raid Arrays by the Intel Raid tool. I was seeing 2 separate disks in windows computer management and all of the support tools I thru at the drive, but only had 1 physical disk in the system. When I opened the disk with the raid tool I found that there were 2 raid arrays configured on the disk. After deleting the raid arrays the disk presented itself to windows as 1 disk.

!!!!!!!!!!!!!Note Removing Raid configuration from the disk wipes the disk!!!!!!!!!!! so backup before doing this.
Adam