Trying to Restore Windows Boot after Dual Booting

[mlloyd22]

I posted this to reddit but thought I would post here as well. Any and all help is appreciated!

I recently wanted to try out Ubuntu again. I'd done this before in the past and used the same method: I went to my windows storage manager and took out roughly 17 GB of my healthy windows partition and made a new FAT32 partition and called it "Drive D." I then used a tool called "Universal USB Installer" version 1.9.9.9 and flashed Ubuntu to Drive D, creating a bootable drive now called "UUI." To access Ubuntu, I simply restarted my computer and went into the boot manager and selected this new bootable drive and clicked "Try Ubuntu." All was going smoothly, until I tried to get back to Windows. I restarted and went into BIOS boot manager to select my windows partition and... there were NO bootable options. Windows, linux, both gone.


Now, from all the helpful replies on my last post, I was able to get back into Ubuntu using a USB stick flashed with Super Grub2 Disk (I used Etcher for that, much more widely recommended than the Universal USB installer tool). Once back in Ubuntu, I used the boot repair tool https://help.ubuntu.com/community/Boot-Repair, and was given the following link: https://paste.ubuntu.com/p/Hh2cJ9Q33X/


I was told to drop this link in a forum, and get help from people much smarter than I! The good news is on Ubuntu, I can see my drive that contains Windows named "Seagate FireCuda SSHD," that sign of life was encouraging. But now I am not really sure what to do from here. Any tips on how I can get back into windows from where I am at?

[oldfred]

You have UEFI system with gpt partitioned drives.
Only MBR drive is sdb, your SuperGrub drive.

Windows only boots in UEFI boot mode from gpt partitioned drives.
It looks like you have Windows UEFI boot in p2 which is shown as the ESP - efi system partition.
But UEFI entry in UEFI, looks like Windows was disconnected and new UEFI entry not created. Most UEFI find Windows in ESP & add UEFI entry if missing, but never seem to find any other systems.

This should add a Windows entry:
sudo efibootmgr -c -L "Windows Boot Manager" -l "\EFI\Microsoft\Boot\bootmgfw.efi" -d /dev/nvme0n1 -p 2

Using a hard drive with installs already and then a partition for the installer, is a bit advanced.
With UEFI you have to switch ESP to the installer partition. But if install does not work for any reason, you have difficulty switching back to original ESP.
And installer may choose wrong ESP to install grub into. You want it in same ESP as Windows UEFI boot files, not in installer's temporary ESP.
Creation of install partition with tool your used also created BIOS boot options using syslinux. Recent versions of Ubuntu are using grub for both UEFI & old BIOS boot.

For most users better to use a USB flash drive or faster external SSD. (I now like external SSD with full install & ISO for installs).

If you have two or more drives, better to put installer on different drive.
UEFI boots external drives & installer using name or label of drive, not "ubuntu" entry. Full install to internal drive uses "ubuntu" entry. Some installs to external drives may create entry "ubuntu" and add boot files into internal drive's ESP confusing boot if external drive not plugged in.

[mlloyd22]

Oldfred,

Thank you for your response. Simply by reading it I now understand I jumped into the deep end, when I really needed to be in the kitty pool with floaties! That being said, I did what you said and seemed to have done it right, I didn't receive any errors. However, when I restarted my machine after the fact and tried any of the long list of boot options in Super Grub2 Disk, none of them opened windows. I still am only able to open up Ubuntu with grub. Is there maybe a specific way I can use the terminal to access my windows drive? Like I said earlier, Ubuntu recognizes my Seagate FireCude SSHD and I am hoping the command you specified truly did restore it's Window's boot entry, but I am just not accessing it right. Do you have any more help you can give me? Should I have my BIOS set to legacy or UEFI? Are there any other pieces of information you could use that would help you solve my predicament? It seems as though you are my last hope, as you're the only one who has responded. Any and all help would be greatly appreciated. Thanks so much.

[oldfred]

Can you boot Windows directly from UEFI boot menu? The same menu you use to choose USB boot for installer.
Windows should have an UEFI boot entry if you ran the efibootmgr command.

In Ubuntu this will show UEFI boot entries, with details on which ESP and boot file is used.
sudo efibootmgr -v

Windows only boots in UEFI mode from gpt partitioned drives. Since you have UEFI and UEFI installs, you must not use legacy/BIOS/CSM to boot.
CSM - UEFI Compatibility Support Module (CSM), which emulates a BIOS mode

New systems since about 2020 are UEFI only. My Dell laptop says "BIOS" but in BIOS it says it will only boot in UEFI mode.

[tea for one]

The good news is on Ubuntu, I can see my drive that contains Windows named "Seagate FireCuda SSHD," that sign of life was encouraging.

Line 231 - sda1 e0905629-3373-465d-9306-f03c4e980a3f Microsoft reserved partition
Line 232 - sda2 ntfs 1210446C104458BD 77d5a413-f1ab-4f65-91d3-644f4ac531f6 Seagate FireCuda SSHD Basic data partition

From the info in the boot-repair report, this disk is sda.
If sda2 is your Windows OS, then sda1 would be an EFI partition?

Assuming the PC originally had Windows on one disk, it is unusual to see your EFI partition on nvme0n1p2 if your Windows OS is on sda2?

Line 107 - 0 OS detected
Boot-repair did not report the existence of any OS and, therefore, it is not clear where your Windows system is located.

If you are sure that sda contains your Windows OS, then power off the PC, remove all other disks and see if it boots?

[oldfred]

Windows is known to do something like Ubuntu's grub in that it will install its boot files to a default UEFI boot drive.
It seems to know default drive setting in UEFI/BIOS. But then if user installs to another drive, it creates the boot on default drive. That is not common, I have only seen it a few times. But most only have one drive. Once or twice it just overwrote part of a Linux partition as it did not correctly see that partition on the "boot" drive.

Microsoft also always has to have a Microsoft reserved partition before the main NTFS partition when using gpt which is required for UEFI boot.
Back in BIOS/MBR days, grub & Windows often had conflicts where grub would put part of grub into sectors just after MBR, but Windows would put hidden info in same sectors. Grub ended up writing around that.
But now with gpt, grub uses bios_grub or ESP, and Windows uses Microsoft reserved and ESP, so no conflicts. Both use ESP - efi system partition, but in different folders for UEFI boot.

Order on drive is important: msftres
https://en.wikipedia.org/wiki/Micros...rved_Partition

[tea for one]

Line 215 - nvme0n1:250GB:nvme:512:512:gpt:Samsung SSD 960 EVO 250GB:pmbr_boot;
If Windows (UEFI mode) is located on nvme0n1, then the disk flag pmbr_boot should be removed?

[oldfred]

I think the pmbr_boot flag is just for grub in BIOS boot on gpt drives.
So yes that flag should be off. Only UEFI boot should be used.

Often Windows install has first partition as some sort of recovery, the ESP, the Reserved partition, the actual install or c: "drive" and then another recovery and/or a vendor recovery partition at end of drive. Do not fully understand all the Windows recovery partitions.

[mlloyd22]

tea for one,

Thanks for joining in the effort to help me. I appreciate it. I will point out that I am fairly certain windows is NOT on the Samsung SSD (nor has it ever been). That's just a hard drive I have for extra storage. I am pretty sure that my Windows OS is on the Seagate FireCuda SSHD.

[mlloyd22]

oldfred,

Here is the output of the command "sudo efibootmgr -v": https://paste.ubuntu.com/p/bhnq7Pbp3Y/

Maybe this will shed some insight. Thanks for all of your help as always.