Question Unable to delete partitions from repurposed OS drive

edwjohn3

Commendable
Jul 22, 2017
29
2
1,545
2
Hi All,

I just put together my new PC build with a new 2 TB SSD to be used as the OS drive. I scavenged the OS install drive from my old PC which I will be using in the new PC for data and extra game installs.

When I booted from the Windows 10 installation media USB and got to the part where I had to choose where to install Windows, I could see that there were 3 partitions on the old 1TB drive - the main big one and then two small ones which I figured were just Windows 10 reserved partitions. I picked the new 2TB drive and moved on, figuring I would delete everything off the 1TB drive later through Disk Management.

Now, once I boot into Windows from the 2TB drive and go into Disk Managment, I am unable to delete the smaller partitions from the 1TB drive because Windows is telling me they are in use. I was not expecting this since I am running Windows 10 from the new 2TB drive. My only thought is that perhaps the Windows 10 installer detected the Windows 10 reserved partitions on the other drive and perhaps "piggy-backed" the new OS install onto them instead of creating new partitions on the new 2TB drive. There is only 1 partition on the new drive, which I think may support this theory.

Is my only option to start over again, this time deleting all the partitions off the old drive from within the Windows 10 install utility before choosing the 2TB drive as the install location?

Thanks,
Edwin
 
Now, once I boot into Windows from the 2TB drive and go into Disk Managment, I am unable to delete the smaller partitions from the 1TB drive because Windows is telling me they are in use.
Can you show screenshot from Disk Management?
(upload to imgur.com and post link)

Some partitions, necessary for booting the system, you will not be able to delete (and you don't need to delete them).
 

edwjohn3

Commendable
Jul 22, 2017
29
2
1,545
2
Can you show screenshot from Disk Management?
(upload to imgur.com and post link)

Some partitions, necessary for booting the system, you will not be able to delete (and you don't need to delete them).
I'm pretty sure that is what's going on here. I just don't want to have OS required partitions living on a separate physical drive than the OS itself.
 
A clean windows install should give you the option to wipe the target drive first.
I would install again, using that option.

And, do not have any other drive connected while you install windows.
If you have a second drive connected, windows will put a hidden recovery partition on that drive, making it impossible to boot without that drive present.
 

edwjohn3

Commendable
Jul 22, 2017
29
2
1,545
2
A clean windows install should give you the option to wipe the target drive first.
I would install again, using that option.

And, do not have any other drive connected while you install windows.
If you have a second drive connected, windows will put a hidden recovery partition on that drive, making it impossible to boot without that drive present.
Is there any way to have Windows not put the hidden recovery partition on the other drive? This is a mini ITX build that was a huge pain to cram into the case and the second SSD is underneath the motherboard. I would really like to avoid taking it apart to disconnect that drive during the Windows install.
 
Love those ITX builds.
I have done a couple.
What is your case, and what are the components?

I do not know how to avoid using the second drive if it is present.
I am assuming it is a m.2 drive so one can not simply disconnect a power or signal cable.

To do things right, I think you need to take the time to remove the drive.
My usual build practice is to assemble everything outside of the case and even install the os and overclock it outside of the case.
Then, also, I like one single large C drive space to manage.
 
I wonder if I could disable the underside m.2 slot in BIOS during the OS install....
Good idea.
Disable it in the BIOS if you can BEFORE you try to reinstall windows.
When you enable the drive later, the partitions may still be there from a previous attempt.
You should be able to later format the drive to get rid of the old partitions.

It is worth a try.
 

onespeedbiker

Respectable
Apr 13, 2019
2,335
176
2,390
133
Yes, when you installed Windows it used the old boot partition, so Windows is now spread over two drives; this is why you should always disconnect any drive besides the target drive when installing Windows. Best fix is to disconnect the old drive and reinstall Windows on the new drive.

After that, I would get a hdd USB enclosure (they make them for m.2 drives), so you can plug in the old drive as an exterior drive after you have booted from the new drive. Once this is done, you can use diskpart or some third party partition software to clean you old drive.
 

edwjohn3

Commendable
Jul 22, 2017
29
2
1,545
2
what exactly are your system specs? including drives, case, etc.
Ryzen 5 3600
Cryorig C7G cooler
AMD Radeon Vega56 reference style blower card
Asus ROG Strix X570-I motherboard
32 gigs Crucial Ballistix DDR4 3600Mhz
ADATA XPG SX8200Pro 2TB (new drive)
ADATA XPG SX8200Pro 1TB (was the OS drive in my old PC)
Corsair SF600 Platinum SFX power supply

All in a Zaber Sentry 2.0 case
 
i have always had 3+ drives installed for the last 10+ years. have never had a problem with unnecessary partitions/data(backup, system restore, boot info, etc) being created on anything but my main OS drive with new Windows installations. if it happens now, i would guess it is because the system partition is already there on the 1TB drive and Windows is just reading that and amending it with the new install.

to avoid disassembling the system to access the drive;
try using a 3rd party disk management software that will work outside of Windows, maybe something like EaseUS Partition Master will work, to wipe the 1TB drive.
then disable the drive in the BIOS if possible.
then if Windows has any trouble booting, use one of it's repair options to try and add whatever it is lacking from the 1TB drive to the new 2TB drive.
if a repair isn't an option, reinstall.
then re-enable the 1TB drive again afterwards.
 
Last edited:

onespeedbiker

Respectable
Apr 13, 2019
2,335
176
2,390
133
When Windows 10 installs in a PC with both an OS drive and target drive, it is not unusual Windows will not create a second boot partition. This is because the non-target OS drive is identified by the BIOS as a boot drive.
 

Colif

Win 10 Master
Moderator
That disk management screen shot might have stopped the guessing :)

Although I warn people against having drives attached when installing win 10, I have not had this problem myself. I think it really depends if the 2nd drive has any spare space on it that isn't partitioned already. If win 10 can perhaps squeeze and EFI into the tiny space left between partitions, it might try.

but then.. i have 128mb free on my hdd and efi is only 100mb, but it still chose the ssd. So apart from the obvious (there was already an OS on other hdd), I am not sure what makes it choose one drive instead of where C is. I think making it as full of data as possible might be one way to stop it?
 

edwjohn3

Commendable
Jul 22, 2017
29
2
1,545
2
Problem solved.

I did another new Windows 10 install from the USB key installer and this time deleted all partitions on both SSDs from within the install utility before picking the 2TB drive as the target for the new Windows installation. It put all the Windows related partitions on my desired drive, and then I was able to turn the whole 1TB drive into a simple volume through Disk Management afterwards.

Thanks everyone for the help.
 
Reactions: JohnBonhamsGhost

ASK THE COMMUNITY

TRENDING THREADS