Windows 10: How to create - or convert - partitions in a Legacy MBR/BIOS setup

Discus and support How to create - or convert - partitions in a Legacy MBR/BIOS setup in Windows 10 Drivers and Hardware to solve the problem; I have just upgraded a Lenovo T430 laptop from Win7 Pro to Win10 Pro (version 20H2) with the excellent help of Brink's tutorial. I chose an in-place... Discussion in 'Windows 10 Drivers and Hardware' started by br1anstorm, May 15, 2021.

  1. How to create - or convert - partitions in a Legacy MBR/BIOS setup


    I have just upgraded a Lenovo T430 laptop from Win7 Pro to Win10 Pro (version 20H2) with the excellent help of Brink's tutorial. I chose an in-place upgrade as I wanted to retain some of the settings and apps from the Win7 setup (I have no critical personal data on this machine). This meant that much of the OEM Lenovo tools and apps were also retained. I kept the Legacy/MBR disk configuration because I prefer - and am more familar with - that than UEFI/GPT. I left the partitioning to the upgrade process. All worked well, and Win10 now runs happily. I was however slightly surprised to see that the disk has four primary partitions. This is a bit tiresome, as I plan to install Linux in a dual boot setup (as I have on other computers). For that I need to create more partitions. But at present I cannot do so! Linux will run from a logical partition. But in order to modify the existing partition arrangements (basically to create an extended partition and more logical partitions within it for Linux), I will have to either delete or convert one of the four existing primary partitions. Here is a screenshot from Win10 Disk Management of my current disk partitioning: Now..... obviously I cannot mess with the System Reserved primary partition (D: - or sda1 in Linux-speak). I will have scope to shrink the C: partition (sda3) where Win10 resides, in order to make space for Linux. But before doing so I will have to do something with one or other of the two remaining primary partitions, because I need to create an extended partition, with logical partitions inside it) for Linux. So.... I have a 12.55GB "Recovery" partition (Q: - or sda2) which is 96% full. And I have another partition of just 624MB which has no drive letter in the Windows system (sda4 in Linux). It is described as 'Recovery partition' and is totally empty. I cannot figure out how and why there are these two partitions - both supposedly to do with recovery. NB As a Linux user (but no expert) I have looked at the disk using GParted, and I note that this last partition, sda4, has the "diag" flag on it. Not sure I fully understand what that implies..... Before embarking on this, I'd welcome advice. It seems to me I have two options: 1) delete this last, unlabelled 624MB primary partition to make it 'unallocated space'; then shrink the adjacent C: partition as much as Win10 will allow, to give me more space; and create a new extended partition in that space - in which i can then organise the necessary further logical partitions needed for a Linux install. Or.... 2) "convert" that unlabelled partition from primary to logical (which I think will need 3rd party software like Easeus or Minitool Partition Wizard); then shrink the C: partition, and expand and reconfigure the extended/logical partition into that space. The first route seems the simpler and easier (I don't entirely trust third party tools). But is there anything I have overlooked? I am just puzzled as to why this fourth unlabelled - supposedly recovery - partition exists, and uncertain as to whether I should mess with it or the 'diag' flag it carries. Any comments and advice will be appreciated. I believe in the "check three times, measure twice, cut once" approach, especially when working on disk partitions!

    :)
     
    br1anstorm, May 15, 2021
    #1
  2. Smittychat., May 15, 2021
    #2
  3. clone MBR HD to bootable GPT partition?

    Hi,

    1. You cannot convert mbr to gpt without data loss. otherwise, you can follow directions here:

    FROM WINDOWS RECOVERY CONSOLE:

    To change a master boot record disk into a GUID partition table disk using a command line


    • Back up or move the data on the basic master boot record (MBR) disk you want to convert into a GUID partition table (GPT) disk.

    • Open an elevated command prompt (right-click Command Prompt, and then click Run as Administrator) and type diskpart. If the disk does not contain any partitions or volumes, skip to step 6.

    • At the DISKPART prompt, type list disk. Make note of the disk number you want to convert.

    • At the DISKPART prompt, type select disk <disknumber>.

    • At the DISKPART prompt, type clean.

    2. I'd suggest converting your vista drive to a virtual machine, load that up on your windows 10 system and use a program like virtualbox to run it.
     
    CoatH4nger, May 15, 2021
    #3
  4. topgundcp Win User

    How to create - or convert - partitions in a Legacy MBR/BIOS setup

    can i convert the disk to mbr and install Windows


    It 's better to let Windows do all that work for you ie. create the needed partitions whether you want to install using GPT or MBR. Here's the steps.
    1. Make sure to disconnect all HD's/SSD's except the one you plan to install Windows.
    2. In BIOS: disable Secure Boot. Set to UEFI if you want to install Windows in UEFI Mode otherwise set it to the legacy BIOS.
    3. Boot the installation USB/DVD. Select the boot mode as shown in screen shot. It's important that you select the correct one so Windows will initialize the disk appropriately (GPT/MBR)

      How to create - or convert - partitions in a Legacy MBR/BIOS setup [​IMG]
    4. On the first screen, press and hold SHIFT key + F10. Command Windows pops up
    5. diskpart
    6. select disk 0
    7. clean
    8. exit
    9. exit
    10. Continue with the installation, click on Custom Installation and select the unallocated partition (disk 0). Do not format, click next and let Windows creates the needed partitions
     
    topgundcp, May 15, 2021
    #4
Thema:

How to create - or convert - partitions in a Legacy MBR/BIOS setup

Loading...
  1. How to create - or convert - partitions in a Legacy MBR/BIOS setup - Similar Threads - create convert partitions

  2. what will happen to legacy bios if I convert mbr to gpt?

    in Windows 10 Gaming
    what will happen to legacy bios if I convert mbr to gpt?: Hi, i am Raghav i had a query in my mind that if i converted my mbr partition to gpt partition then what will happen to:1.OS Windows 102.My apps3.My files4.BIOS legacy...
  3. what will happen to legacy bios if I convert mbr to gpt?

    in Windows 10 Software and Apps
    what will happen to legacy bios if I convert mbr to gpt?: Hi, i am Raghav i had a query in my mind that if i converted my mbr partition to gpt partition then what will happen to:1.OS Windows 102.My apps3.My files4.BIOS legacy...
  4. what will happen to legacy bios if I convert mbr to gpt?

    in Windows 10 BSOD Crashes and Debugging
    what will happen to legacy bios if I convert mbr to gpt?: Hi, i am Raghav i had a query in my mind that if i converted my mbr partition to gpt partition then what will happen to:1.OS Windows 102.My apps3.My files4.BIOS legacy...
  5. Stuck at BIOS menu and asking for MBR convert

    in Windows 10 Drivers and Hardware
    Stuck at BIOS menu and asking for MBR convert: I am Move my Windows 10 from HDD to SSD using this guide but when moved and rebooted, stuck at the BIOS menu and asking for MBR convert. 182189
  6. Novice question on MBR/Legacy installation System Partition

    in Windows 10 Installation and Upgrade
    Novice question on MBR/Legacy installation System Partition: Novice question on MBR/Legacy installation System Partition Greetings. Recently did a fresh installation on an ancient MBR/Legacy machine using the latest 1909 ISO. The process created a 579 MB System Partition consisting of two folders, Boot and Recovery, among other...
  7. Convert legacy bios to uefi on old fashioned install

    in Windows 10 Support
    Convert legacy bios to uefi on old fashioned install: I know to convert legacy bios to uefi using mbr2gpt IF the legacy bios has a separate system partition but it does not work for old fashioned legacy bios installs where there is not a separate partition. I also know how to do it the older way with Macrium Reflect i.e. image...
  8. Is It Possible To Convert GPT to MBR Than Legacy Boot Windows

    in Windows 10 Installation and Upgrade
    Is It Possible To Convert GPT to MBR Than Legacy Boot Windows: First off, I apologize if this may be posted int the wrong section, I could not find another section that would suit this content. And also, I apologize if this sounds stupid, I don't like staring at the Acer logo when I turn on the computer, and cannot find a way to turn it...
  9. how to convert MBR to GPT?

    in Windows 10 Installation and Upgrade
    how to convert MBR to GPT?: hi I have a problem in installing Windows 10 from usb drive. Error is "windows cannot be installed to this disk. the selected disk has MBR partition table. on efi system windows can only installed to GPT disk" I have formatted without aware this issue. I have few...
  10. utility to convert MBR disk with Windows partitions to GPT?

    in Windows 10 Installation and Upgrade
    utility to convert MBR disk with Windows partitions to GPT?: Does this utility exist? I've tried Minitool's free version, which claims to support MBR to GPT conversion, but I got a warning that the disk would not be bootable. I downloaded a trial of the paid Easeus partition manager and when I tried that conversion, I got an...