Dual Boot ended up in a big mess

I have:
1 SSD 860EVO that is Disk 0 with Windows 10 Pro. The first partition no drive letter 100 MB Healthy (EFI System Partition), My PC (C:) 930.90 GB NTFS Healthy (Boot, Page File, Crash Di,[, Basic Data Partition), last partition no drive letter 500 MB Healthy (Recovery Partition)

1 Samsung 2 TB HHD that is Disk 1 used for Backup (I:) 1331.22 GB free of 1863.01 GB NTFS

1 Samsung 1TB HHD that is Disk 2 931.51 GB Online was divided into 4 fairly equal partitions.
E: My Documents 336 GB free of 490 GB,
F: My Downloads 22.3 GB free of 98.5 GB, (was originally much larger before the DB install)
G: Program Apps 57.2 GB free of 60.2 GB,
H: Website Files 160 GB free of 242 GB
now (F:) is as shown below:
The Zorin installer took Disk 2 F: My Downloads and split it as follows:
between E: & F: have 8 MB Unallocated,
between F: & G: have 8 MG Free Space,
between G: & H: have (J:) 513 MB Fat32 Healthy (Logical Drive) & (new partition no drive letter) 39.31 GB Healthy (Primary Partition) ending with H:

After the install finished I restarted it and it was showing the Dual Boot Menu with several Zorin choices and the last choice is C: Windows 10. After playing around with Zorin I clicked on Restart and selected Windows 10. It would not boot into Windows ending up booting back into Zorin. Tried it several times. I had to warm boot and F12 then selected C: to get back into Windows 10.

Where is this dual boot menu installed? I assume I can just delete the added partitions (in some certain order and merge) used by Zorin, how do I get all this back where Windows 10 will boot, and in what steps?

What I want to do is remove Zorin 16 Pro & put Disk 2 back as it was. Need help here so Windows 10 will boot.

Install Zorin 16 Pro on Disk 0 to share equal space with C: Windows 10. After getting Z16Pro working will delete windows and use its space as needed.

How did this happen, I was very careful to select Disk 0 to dual boot. It was easy to see SSD 860 from the Samsung HDD drive. Is this going to happen again if so I can unplug this disk while doing the install?

I have tried to include everything in great detail. I have a good working knowledge of Windows and barely know anything dealing with Zorin so please don't leave out the newbie steps. I do know what a terminal is and how to type code in one that about it. I am not giving up this time if there are drivers for all my devices.


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Ok, the 532MB partition on disk 2 is the grub menu. This partition, being on a seperate drive, can see that there is a windows but cannot interact with it. In order to correctly duel boot we will have to make a few changes.

Boot your live image -> choose install (now relax, we won't be installing anything but the bootloader in the proper place for dual boot) -> go through it like you were doing a regular install, but use the something else method.

Here is where you'll see the difference. In the partition window at the top, ensure disk 0 partition 1 is your efi for windows (100mb). In the bottom of that window it asks where to install the bootloader... choose sdap1 or whatever naming method it uses. In the window at the top, scroll down till you see disk 2 and select the ext4 partition. Hit the gear at the bottom left of the window. Change it from do not use to ext4, mount point /, do NOT format (unchecked format option).

Scroll down to the 532MB partition, select it and hit the minus. This will delete it. Leave everything else as it is. Install. Reboot and choose.

Forgive me, i didn't see it till i reread, you want zorin on disk 0. The changes zorin made to disk 2 cannot be undone. The partition overwrite data that existed there with a different file system, meaning those blocks/ sectors were changed (written to) and cannot be undone. The instruction above will use your system as it sits.

To change the windows partition and install on disk 0 will not give you any ability to restore what was removed.


If you really would like to install to disk 0 you should read:

After performing all these steps, boot into the live image, open gparted [disks] (administration or system menu category). Select the windows partition (not efi, system or recovery), right click n choose resize and drag it from the right to the left. You may also be able to divide the offered number by 2 and type in the size. In the unallocated area (you may have to write the changes first) right click and create partition. It will default to the full size, format as ext4. Close disks and hit install. Use the something else method. Same as above, choose the 100 mb efi for bootloader. In top window choose disk 0 ext4 partition and mark as root (/). No need to format. Scroll down and delete disk 2 532mb and the ext4 partition, create partition there and format as ntfs, don't mount. This will get you a you want it, but nothing will be in that partition you just created. That data is gone.

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I finally have had time to work on this project. Didn't go well at all. I have taken screenshots to show what I got that was way different looking to me than as described above. I will get these up sometime on Saturday. I now have to reinstall Windows or do an install backup to get windows able to boot. I have orders to process and a bunch of sales brochures to print out.

I think it will be faster to just put everything back as it was, to begin with then install again correctly. I have got to find out how to find Secure Boot to turn off. I have a Gigabyte AX370 5 gaming and do not find anything that disables this and it will turn off secure boot. I read the manual and it does not mention secure boot at all in the Bios area.
My Disk 0 is SSD and I would rather have both OS on the same drive. I have not lost any files on (F:) Zorin just made space on the on (F:) It won't take very long at all to put (F:) back as it was.

This page suggests the following method, scrolling down to Gigabyte:

I have My (F:) drive redone as it was before. I am now ready to install Zorin16 Pro on (C:) drive as dual boot with windows 10. Is it my understanding you do not use the choice dual boot use the something else choice?

Here is My Gigabyte AX370 dealing with I assume Secure Boot: Notice that the choices are Disabled, Enable, or Legacy Only. Which ones should I change and select? Is changing this a must or can I wait and do it after I get Zorin running to where I can dump windows? If this is changed does Drive 0 (C:) need to be changed from GPT to MBR?

>>Windows 10 Features
Allows you to select the operating system to be installed. (Default: Other OS)
>>CSM Support
Enables or disables UEFI CSM (Compatibility Support Module) to support a legacy PC boot process.
eEnabled Enables UEFI CSM. (Default)
eDisabled Disables UEFI CSM and supports UEFI BIOS boot process only.
This item is configurable only when Windows 10 Features is set to Windows 10 or Windows 10 WHQL.
>>LAN PXE Boot Option ROM
Allows you to select whether to enable the legacy option ROM for the LAN controller. (Default: Disabled)
This item is configurable only when CSM Support is set to Enabled.
>>Storage Boot Option Control
Allows you to select whether to enable the UEFI or legacy option ROM for the storage device controller.
eDisabled Disables option ROM.
eUEFI Only Enables UEFI option ROM only.
eLegacy Only Enables legacy option ROM only. (Default)
This item is configurable only when CSM Support is set to Enabled
>>Other PCI Device ROM Priority
Allows you to select whether to enable the UEFI or Legacy option ROM for the PCI device controller other than the LAN, storage device, and graphics controllers.
eDisabled Disables option ROM.
eUEFI Only Enables UEFI option ROM only. (Default)
eLegacy Only Enables legacy option ROM only.
This item is configurable only when CSM Support is set to Enabled.

IF Windows is installed as EFI, not as Legacy, then:

This suggests Windows is installed as EFI, so Zorin should also be installed as EFI, not as Legacy (MBR).
You should set the EFI settings first, then install Zorin OS. If you need, you can change the EFI settings later.

If Secure boot is not listed, the motherboard may not support it...

This is entirely your choice. If you want Windows and Zorin OS to be divided equally on the drive, you can choose "Install alongside". If you want to take control over how much of the drive each installation gets, giving the lions share to one OS over the other, choose the "Something else" option and size the partitions as you want them to be.

Still no install Zorin OS. I get the "No root file is defined" error when selecting my (C:) drive. This drive is 1 TB Disk 0, GPT, Primary. Has Fat32 100 MB Healthy EFI Sys Part., (C:) 930.90 NIFS, Last 500 MB Recovery also Fat32.

On Installing Zorin it will pick a drive with free space that is MBR and will install there (this is what happen the first time) If you select Disk 0 which is GPT you will end up getting the NO Root error due to the Fat 32 windows boot partition.
This is a bug in the Zorin installer software that should be fixed.

I have not tried this yet but I bet if I change Disk 0 from GPT to MBR (using EasyUS Master Partition tool) that Zorin will install as Dual Boot with no problems. What I don't know is will the computer now boot into windows using MBR. I would guess EasyUS builds the proper boot file to boot the computer otherwise what would be the purpose. I will try making the change to MBR and see it Windows will boot. If it does I will try to install Zorin.

It has nothing to do with gpt or mbr. Do not switch to mbr, you'll have more issues. Stay with gpt.

In the installer, where it asks for the bootloader with the partitions above, you want to select the efi partition (100MB) that windows uses, otherwise you'll be switching boot devices to change os, it's not practical.

In the window of partitions, above where you choose the bootloader location, in something else, scroll down till you see your partition, will have to be by size since drive letters are in the os only. Select it. Immediately under the window on the left you'll see a + - and gear icons, choose the gear (modify partition).

Make sure it's the right partition. The size will be in MB. Divide 1024 from GB amount to get MB.
The mount point will be / ... that's root.
Format it as ext4. Hit ok. It will warn you that it has to be written to disk to continue. Click ok.

If you have a data partition, somewhere setup to store files to be shared between the os's, it should be ntfs and mounted on /mnt/[your- name-for-dtorage]. Make sure you change the bracketed text to whatever you want to name it.

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Make sure you check all the following first:

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I did switch but felt years ago that it was a better boot system. Glad to hear you say do not do it. I will switch back to gpt. When the boot record is kept in a different partition just makes good sense you have less chance getting it corrupted than mbr where boot record occupies the first part of Drive C:

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I do want the Linux boot loader to be separate I will use EasyBDC to tie Windows and Zorin as Dual Boot, that is the easy part.
I have no problem selecting the correct partition to install Linux in. The problem I have is I see the + , - and the word Change all of which are grayed out. There is no Gear to click on. Do you think there is something wrong with my zorin image?
What I have now is a GPT Disk 0 a 298 Mb EFI Fat32, My PC (C:) Windows 10 488.29 GB NTFS leaving 442 GB unallocated space for Zorin. I will boot into Zorin and try to install it.

It looks like this installer does not like unallocated space. I have quit and will make two partitions one about 100 MB Fat 32 the other NYFS what's left. Then try again.

Although it is not common, I have seen it happen where the Ubiquity Installer has trouble with Free Space- Formatting that free space first to ext4, just as a blank format, then running the installer seems to work.
It's worth a shot.

Selecting a partition in the top window will give you access to the add, remove and change options under the window. Without a selection they will be greyed out.

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Need Help Please: Have tried everything in my tool closet and have been able after about 15+ installs, to install Zorin 16 Pro, and now on startup will boot into a Zorin Dual Boot Menu. It will boot into Windows 10 but will not boot into Zorin.
What I have done is installed the Linux EFI bootloader to the newly created EFI partition. My computer at this point is supposed to boot into Zorin unless I pick Windows 10.
What I have not done is alter Windows 10 install or Bootloader or even so much as touch the Windows 10 10 EFI partition.
When Zorin is selected it attempts to boot and finally locks up in Gigabyte's boot screen. Acts as if no boot record. On the Installation menu I told it to put the boot file in the new EFI partition.

By placing the bootloader in another partition, the only way to boot into zorin is by changing the boot order/device each time. It cannot find the bootloader because it's looking for it in the windows efi partition. You must either install grub into the windows efi or change boot order/device on each boot.

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What do you mean "or change boot order/device on each boot. Where can I go to check if it will start before I install again?

Like booting into the live image, you have to choose which "device" to boot from... even if it is only a different partition. Hit f12 (may be different for you) to choose the boot location. If that doesn't work, go into the bios and change it there, it will be listed. But you will have to do that every time you boot.