Question about 2 windows installations

[Megaone]

Long story-short: my main drive (with the OS, windows 10) is broken but still somewhat functional. I installed a new copy on windows 10 onto another drive and started setting it up while slowly backing up stuff from the broken drive.

Anyway apparently when I installed the second copy of windows 10, it somehow got "tied" to the original install on the broken drive, so much so that when I go into the BIOS to choose the boot device, I can only choose the broken drive and not the other one with the second OS. It seems like the OS always has to boot from the broken drive and only after that first step it gives me the option to choose which windows 10 installation I want to boot into (it presents me with 2 windows 10 installs on 2 different volumes). This is a problem because I obviously want to get rid of the broken drive (because it's broken) after I backup all I can but looks like as soon as I disconnect it, the other windows install on the other drive will also stop working.

 

I don't know why installing windows on a separate drive somehow tied it to the other windows install but this is annoying. I there any way I can keep the second windows install after I remove the broken drive?

[AndrewAsd]

The EFI partition is probably located on the broken drive and when you installed another Windows version on a separate drive it made use of that EFI partition for booting instead of making a new one on your new drive. You can try to recreate that EFI partition on your new drive or reinstall Windows on that new drive with the broken drive removed from the system so it creates that EFI partition on the new drive and doesn't make use of the existing one on the broken drive.

[Kilrah]

Yep. Always physically disconnect all drives other than the one you want to install to if you want a clean independent install, then put them back afterwards. 

[Megaone]

18 minutes ago, AndrewAsd said:

The EFI partition is probably located on the broken drive and when you installed another Windows version on a separate drive it made use of that EFI partition for booting instead of making a new one on your new drive. You can try to recreate that EFI partition on your new drive or reinstall Windows on that new drive with the broken drive removed from the system so it creates that EFI partition on the new drive and doesn't make use of the existing one on the broken drive.

Ok so once I have no more need for the broken drive, I can remove it but won't be able to boot into the windows on the second drive. How would I fix that? Using the USB pen I used to install it? Will it fix it without resetting or deleting anything already on the drive?

[Megaone]

14 minutes ago, Kilrah said:

Yep. Always physically disconnect all drives other than the one you want to install to if you want a clean independent install, then put them back afterwards. 

I didn't even think that would be necessary because I was installing in a completely different drive, thought I'd end up with 2 completely separate windows installations...

[AndrewAsd]

19 minutes ago, Megaone said:

How would I fix that? Using the USB pen I used to install it? Will it fix it without resetting or deleting anything already on the drive?

There's multiple ways to go about it. But basically you need to shrink the size of the disk in windows on your new drive so you have a separate FAT32 partition of about 100mb left over. Then you can boot into the windows usb to get a CMD window which you can then use to create that EFI partition you need. You can follow the video below for more information.

 

[Megaone]

Hmm ok, I'll look into it when the time comes. I'm still in the process of backing up what I can (a delicate process because the SSDs controller is screwed and will crash randomly with high/sustained bursts of activity). Thanks

[Megaone]

Ok so I actually found this nice tutorial that addresses my exact problem, seems fairly straightforward:

 

https://www.winhelponline.com/blog/create-move-efi-partition-windows/

 

My only question is, can this be done directly from the windows environment or do I have to reboot and access the command prompt from outside windows (like say, from the USB pen)?

 

 

[C2dan88]

8 hours ago, Megaone said:

My only question is, can this be done directly from the windows environment or do I have to reboot and access the command prompt from outside windows

You can try that from within windows.

But if the commands errors out I would reboot into windows install media hit Shift+F10 run diskpart command and in place of "select volume C" you'd run something like this

list volume
select volumne 1  <<<< change 1 if your windows partition is listed as a different volume number
assign letter=C

Now run the rest of the commands on that site.

[Megaone]

15 hours ago, C2dan88 said:

You can try that from within windows.

But if the commands errors out I would reboot into windows install media hit Shift+F10 run diskpart command and in place of "select volume C" you'd run something like this

list volume
select volumne 1  <<<< change 1 if your windows partition is listed as a different volume number
assign letter=C

Now run the rest of the commands on that site.

Ok I'm a bit paranoid now but here's what I have so far: I actually went ahead and in the disk management (in windows), I simply shrunk the volume which contains  windows (labeled C) and created a new partition/volume (named it "EFI" with 150MB), labeled Y and I formatted it in FAT32. So now I have the regular C volume and this Y volume, which I now simply have to "convert" into a proper EFI partition, right? Do I just fire up command prompt and run "bcdboot C:\Windows /s Y:"?

 

EDIT: ok I went and did it and it kinda worked (as in, all the required files were created in the Y: volume but the thing is, windows still sees it as a regular partition and not an EFI partition:

As you can see, disk 3 (the broken SSD with the original windows) has an actual EFI partition while the Y one I created in disk 0 (the new SSD with new copy of windows), despite having all the right files inside, still reads as a basic data partition. Do I actually have to disconnect disk 3 from the PC in other for the new EFI partition to take effect? Maybe because you can't have 2 EFI partitions at the same time?

[NoLeafClover]

43 minutes ago, Megaone said:

Maybe because you can't have 2 EFI partitions at the same time?

You absolutely can. In fact, every drive containing an EFI bootable OS should have its own ESP as standard practice.

 

44 minutes ago, Megaone said:

disk 3 (the broken SSD with the original windows) has an actual EFI partition while the Y one I created in disk 0 (the new SSD with new copy of windows), despite having all the right files inside, still reads as a basic data partition

This is because the ESP is a special partition. It must have the GUID value of C12A7328-F81F-11D2-BA4B-00A0C93EC93B.

 

Unfortunately, I don't know how to change it on Windows - I'm sure there's a way. But if you get a live USB stick with Linux it's fairly trivial to change the identifier via a tool such as "gdisk" or any other GUI tool such as "gparted". If that's something you're happy to do, I can elaborate on the steps.

[Megaone]

14 minutes ago, NoLeafClover said:

You absolutely can. In fact, every drive containing an EFI bootable OS should have its own ESP as standard practice.

 

This is because the ESP is a special partition. It must have the GUID value of C12A7328-F81F-11D2-BA4B-00A0C93EC93B.

 

Unfortunately, I don't know how to change it on Windows - I'm sure there's a way. But if you get a live USB stick with Linux it's fairly trivial to change the identifier via a tool such as "gdisk" or any other GUI tool such as "gparted". If that's something you're happy to do, I can elaborate on the steps.

I was just about to give an update because I found this:

 

https://www.winhelponline.com/blog/fix-efi-boot-partition-guid-set-id/

 

So I followed those instructions and it all seemed to work. The partition appeared as an EFI system partition in disk management and it even disappeared from "My PC" (which makes sense because I turned it into a system partition without letter assigned). So I rebooted the PC, went into the BIOS but in the boot options, the only disk that shows up is still the old, broken one. I nevertheless proceeded to windows, checked disk management (still reports it as an EFI system partition without a letter assigned) but when opening "My PC", it's visible again with the letter Y. The only difference is I can't really open it (it says I don't have permission). But it shouldn't even be visible in the first place, what went wrong?

[NoLeafClover]

10 minutes ago, Megaone said:

So I followed those instructions and it all seemed to work. The partition appeared as an EFI system partition in disk management

Nice one!

11 minutes ago, Megaone said:

So I rebooted the PC, went into the BIOS but in the boot options, the only disk that shows up is still the old, broken one.

This probably has to do with the EFI boot entry not having been "restored" properly from the first time. I have experienced this at some point in the past and vaguely remember struggling to recover the boot entry despite the correct files being in the ESP. I do remember dealing with bcdboot from a Windows recovery environment, but I use Windows so rarely I don't think I could help more than that.

18 minutes ago, Megaone said:

when opening "My PC", it's visible again with the letter Y. The only difference is I can't really open it (it says I don't have permission). But it shouldn't even be visible in the first place, what went wrong?

If I were to guess it might be a leftover from when you first assigned the letter Y to it. Then, Windows being crap as always, it got "confused" as there's probably a policy that says "ESP shouldn't be exposed to users" but a volume configuration says that it should have the letter Y.

 

You may be able to unassign Y manually through diskpart:

1. Follow the first steps of the guide you linked to open "diskpart"
2. Type "list vol"
3. Note if there's the letter Y assigned to any of the volumes. If there is, note the volume number. If there isn't, see if you can identify which volume corresponds to the new ESP.
4. Type "select volume N" where N is the number of the volume corresponding to the ESP
5. Type "remove letter=Y"
6. Type "exit"

Hopefully this will unassign Y: for good.

[Megaone]

12 minutes ago, NoLeafClover said:

If I were to guess it might be a leftover from when you first assigned the letter Y to it. Then, Windows being crap as always, it got "confused" as there's probably a policy that says "ESP shouldn't be exposed to users" but a volume configuration says that it should have the letter Y.

 

You may be able to unassign Y manually through diskpart:

1. Follow the first steps of the guide you linked to open "diskpart"
2. Type "list vol"
3. Note if there's the letter Y assigned to any of the volumes. If there is, note the volume number. If there isn't, see if you can identify which volume corresponds to the new ESP.
4. Type "select volume N" where N is the number of the volume corresponding to the ESP
5. Type "remove letter=Y"
6. Type "exit"

Hopefully this will unassign Y: for good.

 

I actually fixed that in the meantime, found a solution here: https://answers.microsoft.com/en-us/windows/forum/all/efi-partition-showing-in-explorer/a12eeb78-45a4-446c-8e3d-e650db6f0634

 

I just ran "mountvol Y: /D" and it worked, I rebooted and no more Y drive in explorer or under diskpart.

 

However, the EFI partition is still not properly configured for some reason. You can see here under diskpart, it shows up as "hidden" instead of "system" (the one that shows up as "system" is the broken one):

 

I even ran the "set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b override" and "gpt attributes=0x8000000000000000" again (after removing the letter assigment) but it's not sticking for some reason

[Megaone]

Came across another forum thread (https://forums.tomshardware.com/threads/can-i-add-an-efi-partition-to-new-ssd-after-i-already-installed-win-10.3766315/#post-22717742) that pretty much repeats what I already did except it did stress that the person needs to disconnect the first/original drive after the whole process, which is exactly what I'm trying to avoid (I was hoping to get everything set up and then later replace the broken SSD at my leisure) but either I'm doing something wrong or you DO have to disconnect the other drive in order for the new one to appear in the BIOS' boot menu

 

I think because there can only be 1 windows boot manager in the BIOS boot menu (not sure, maybe I'm wrong and there can be more) so unless I disconnect the disk currently assigned to it, I can't "switch" it to the other disk, even if I do get the EFI partition all set up

[Megaone]

Well folks, things just sorted themselves out.

 

Basically last night I left the PC on and today the PC was still on but when I turned the monitor on, there was no signal. Turns out the broken SSD must've caused a crash during the night and when it does, it disables itself until you actually power off the PC and turn it on again (you can read more about that in this thread, if you want: https://linustechtips.com/topic/1607833-please-help-me-identify-a-possible-ssd-problem/).

 

Anyway, because it turned itself off, when I rebooted the PC the windows boot manager had no access to it so it automatically switched to the new disk! So now the broken SSD is finally out of the whole boot process! It crashing and turning itself off basically functioned as me physically disconnecting it lol.

[NoLeafClover]

Glad to hear it sorted itself out.

 

Sounds like what may have happened is the boot loader recovery steps you followed created the files in the ESP but never created an EFI boot entry. Failing to boot from the "broken" drive, the BIOS will have attempted the next bootable drive at which point it will have looked at the files in the drive's ESP for a boot loader. This is usually equivalent to selecting just drive, without any specific named entry, from the boot menu.

 

Re number of "Windows Boot Manager" (or other) entries you can have - there's no restrictions on that. These are stored in the BIOS memory and are essentially named pointers to the location of boot loader files, sometimes with additional parameters. The name can be anything, and duplicate names are also allowed.