brent tomscharbach what you are talking about in step 2 is installing efi bootmanager from the SC, then manually removing dead entries, correct? And all but Solus, which I believe is also correct. My research is showing nothing else except use the EFI shell option (bios) to achieve the same thing but I don't know how to talk in that terminal.

I'm getting lost. IF I understand what you are trying to do, you have Solus installed on your computer, and you want to install Windows 10 on a separate drive.

The reason I go into BIOS/UEFI (F2 on my Dell computers, maybe something else in yours) at several points in the process is to clean up the UEFI boot sequence before any installation. BIOS/UEFI gets cluttered over time -- for example, I remember seeing Windows Boot Manager, two instances of Linux Boot Manager, and several Grub entries on my test computer -- and the point is to clean it up, so that when you are done, you have Windows Boot Manager and Linux Boot Manager only as your primary boot managers.

You have Solus installed. Assuming that you don't have any other Linux distros installed, Linux Boot Manager should be the only UEFI boot option. If you have remnants (e.g. on or more Grub entries from former installations), I think that it is a good idea to get rid of them.

Why don't you go into your BIOS, and let me know what you see under "Boot Sequence" or whatever it is called in your BIOS.

    @tomscharbach "IF I understand what you are trying to do, you have Solus installed on your computer, and you want to install Windows 10 on a separate drive."
    Correct.
    "is to clean up the UEFI boot sequence before any installation....and the point is to clean it up, so that when you are done, you have Windows Boot Manager and Linux Boot Manager only as your primary boot managers."
    OK that's on me, I misinterpreted "clean/remove" these entries from posts of yours past as "clean/remove." What you mean is simply tidy boot order. That I can do. I have about 10 entries and as long as SolusPrimary and WinSecondary are 1 and 2, I'm good to go. I can't see a way to remove any boot order entries--only move them.
    That's what I needed to know, thank you.

    As for the spectacular post before that, thank you again. I have someone with W10 in the same room as me and have used her Media Creation Tool to burn the Microsoft-furnished ISOs...but none of the MS tools on those 2 isos (both 'recovery' iso and 'install iso) could fix humpty. Neither would the 'install' iso install; it questioned my validity. So I have another licensed avenue coming.

    (for anybody reading our own woeusb software will burn WIN stuff in Linux ONLY if you NTFS format the usb).

    Thank you so much for indulging me. I have never (like @WetGeek said in another post) wanted to dual boot, but with yor 'inividual' approach it just makes a wild amount of sense to me, especially in the confidence dept.
    If we met in person I'd buy you a Jamesons on the rocks, splash of water, twist of lime, on ice. Take care and I appreciate your thoroughness with your dual boot method.

      brent I misinterpreted "clean/remove" these entries from posts of yours past as "clean/remove." What you mean is simply tidy boot order. That I can do. I have about 10 entries and as long as SolusPrimary and WinSecondary are 1 and 2, I'm good to go. I can't see a way to remove any boot order entries--only move them.
      That's what I needed to know, thank you.

      No, I actually mean "clean/remove", that is, eliminating all the superfluous boot entries. As an example, these screenshots are from my two Solus computers:

      First, a Dell Inspiron laptop (AMD BIOS) on which I have only SOLUS installed:

      Look at the bottom two lines. Note that "UEFI BOOT" shows only one boot manager -- "HDD1-Linux Boot Manager (Dell blah blah blah ...)

      Then look right above to the lines "File Browser Del Boot Option", which allows me to highlight Linux Boot Manager and delete that boot manager. If I had five or six entries under "UEFI Boot", I would use "Del Boot Option" to get rid of everything except "Linux Boot Manager".

      Second, my Optiplex 7070 (custom Dell BIOS for Latitude and Optiplex computers), which is dual boot, Solus and Windows:

      The UEFI has two boot managers available, Linux Boot Manager and Windows Boot Manager. If I highlight either, I can delete it using the "Delete Boot Option".

      If you have 10 entries, I'd consider getting rid of everything except the Linux Boot Manager and the Windows Boot Manager at this point. I'd be most concerned about Grub entries. Most of the other boot options are probably artifacts of your previous sins, installing other distros along the way, and have the potential to muck stuff up if for no other reason than the computer has a list of boot options, most of which are inactive. However, if you can't figure out a way to delete them (every BIOS is different) then so long as Linux Boot Manager and Windows Boot Manager are the top two (that is, primary and secondary) it will probably work out okay.

        brent As for the spectacular post before that, thank you again. I have someone with W10 in the same room as me and have used her Media Creation Tool to burn the Microsoft-furnished ISOs...but none of the MS tools on those 2 isos (both 'recovery' iso and 'install iso) could fix humpty. Neither would the 'install' iso install; it questioned my validity. So I have another licensed avenue coming.

        If I were you, I'd start fresh with a new USB, downloading a fresh copy of the Media Creation Tool (MediaCreationTool21H2.exe) to create a new Windows 10 installation USB. If Windows 10 was installed on your computer at some point in the past, the license (which is persistent once activated) should automatically activate when Windows installs. Something is not right with the other USB if you are getting validation errors unless Windows 10 was not installed and activated on your computer at an earlier time. In any event, if your friend's USB was created more than a 2-3 months ago, it will install an outdated (21H1 or earlier) version of Windows 10, and you will find yourself running updates until the cows come home.

            tomscharbach "wever, if you can't figure out a way to delete them (every BIOS is different) then so long as Linux Boot Manager and Windows Boot Manager are the top two (that is, primary and secondary) it will probably work out okay."

            If I only had that nifty Dell tool....but I don't. My BIOS is different. It's one of those weird ones you can set as UEFI or 'Legacy and UEFI' and has a lot of ECO BS but little function...(I have it set as UEFI).

            tomscharbach If Windows 10 was installed on your computer at some point in the past, the license (which is persistent once activated) should automatically activate when Windows installs. Something is not right with the other USB if you are getting validation errors unless Windows 10 was not installed and activate on your computer at an earlier time.

            Great critical reading---that's the odd thing. The install .iso didn't reject me literally for verification, it simply said 'cannot' or 'will not' 'proceed' with installation. I bought this used rig from a computer repair shop owner. I have to ethically believe he creates his DIY RIGS with a licensed product. I have not asked him. **That's why I'm opting for the fresh install here.

            What's omitted from my story is how I nuked it. When he sold it to me he had a so-called "hybrid" setup with WIN on the SSD and the 'dependent symbiotic slave' (as I understood it) was an HDD with his games on it. I destroyed the "'dependent symbiotic slave' relationship by switching boot order and installing SOLUS on the HDD and 'decativating' the WIN SSD as the primary. Don't ask me what "deactivating" means. It's likely I went into the SSD clumsily swinging an axe. Win 10 never was reachable again.

            Thanks for the ear and attention to detail.

                  If anyone is interested: Get Ventoy for your bootable USB stick. I have 9 or 10 Linux ISOs, W10 & W11 on a single 64GB USB drive. I choose which to boot up from a list.

                    brent I have to ethically believe he creates his DIY RIGS with a licensed product. I have not asked him.

                    If your computer was a custom build, the license he installed might have been a retail license rather than an OEM license. A retail license is not tied to a particular motherboard, unlike an OEM license, and requires a license number for installation. Whatever the case may be, I hope you get it sorted. I have every confidence that you will, and I hope that you'll keep me informed.

                        tomscharbach I hope you get it sorted. I have every confidence that you will

                        you overestimate me😉 but it makes me so happy you've been in this situation to talk to.

                        murbert Get Ventoy for your bootable USB stick. I have 9 or 10 Linux ISOs, W10 & W11 on a single 64GB USB drive.

                        I believe you but this makes no sense at all. It's a tool that makes 85 partitions on demand? So then it can present you with 85 boot options on plug in? [85 being a rhetorical x number of course)].
                        Do you know how much many isos forever destroy a good usb by making permanent write protections and read only forever--never to be cracked by any tool or OS? The answer for me is a lot of USB $$$$$ right down the toilet over the years. Tell me more about Ventoy at yr convenience🙂.

                              brent The ISOs are not installed, just copied over to the drive. All the ISOs are bootable, just as if you had them on their own stick made with Media Creation Tool, Fedora Media Writer, Gnome Disks etc.
                              They can tell you better than I
                              https://www.ventoy.net/en/index.html

                                I used SSD and HDD, One have Linus and other one have windows 10
                                When I boot at start screen it ask me for the OS to load, I have Asus motherboard and make the boot setting with no priority disk

                                brent My BIOS is different. It's one of those weird ones you can set as UEFI or 'Legacy and UEFI' and has a lot of ECO BS but little function...(I have it set as UEFI). ... I have about 10 entries ... I can't see a way to remove any boot order entries--only move them. ... What's omitted from my story is how I nuked it. When he sold it to me he had a so-called "hybrid" setup with WIN on the SSD and the 'dependent symbiotic slave' (as I understood it) was an HDD with his games on it. I destroyed the "'dependent symbiotic slave' relationship by switching boot order and installing SOLUS on the HDD and 'decativating' the WIN SSD as the primary. Don't ask me what "deactivating" means. It's likely I went into the SSD clumsily swinging an axe. Win 10 never was reachable again.

                                It is possible that "deactivating" a boot entry in your BIOS is the equivalent of deleting a boot entry in a different BIOS. If that is the case, then the entry might show up but be non-functional. Researching your BIOS and motherboard might be a good place to start in understanding what is going on.

                                Open the terminal and run: sudo dmidecode

                                BIOS INFORMATION - At the beginning of the resulting output, you will find BIOS Information, for example:

                                BIOS Information
                                Vendor: Dell Inc.
                                Version: 1.10.0
                                Release Date: 09/27/2021

                                MOTHERBOARD INFORMATION -- Farther down, you will find information about the motherboard, for example:

                                Base Board Information
                                Manufacturer: Dell Inc.
                                Product Name: 0C1R19
                                Version: A02

                                With those two bits of information, it might be possible to find information about the BIOS, in particular, that will allow you to remove boot entries or at least understand how to render them non-functional.

                                It is also possible that the man who sold you the computer might be able to provide some advice about how to clean up the mess.

                                    tomscharbach I cut and paste what I needed from dmidecode and will investigate this morning. thanks for that avenue; I had not considered it. It's an American Megatrends bios and an MSI board so I'm sure there is literature to find.

                                        brent It's an American Megatrends bios and an MSI board so I'm sure there is literature to find.

                                        Cool. The American Megatrends and MSI combo is as common as dirt. You'll find something. You might even find a setup/service manual for either/both, which will give you lots of information.

                                            tomscharbach OK, like the Sinatra song, I did it all Your Way. But I'm not done. I have two independent OS's on different drives that function, done to the letter of your tutorial.
                                            I am not attempting to dual boot yet.
                                            I don't know how to get rid of all the boot entries. Found no info for my AMI V.25.2 and my MSI-7817.
                                            What my weird bios DOES have, however, is this UEFI Shell Teminal. It's a terminal. I have no idea what language/commands to use it in. But I bet that's the key. Or is it?
                                            Will research more.

                                                brent I have two independent OS's on different drives that function, done to the letter of your tutorial.
                                                I am not attempting to dual boot yet.

                                                Progress. Assuming that Windows Boot Manager and Linux Boot Manager are the first two entries, in whichever order you prefer, probably Linux Boot Manager first and Windows boot manager second, the computer should boot to whatever OS is the first on the list, with F12 (or whatever key you use to access the boot manager screen) to get to the second on the list.

                                                The first step might be to open the boot manager screen in BIOS and see what it looks like. As I recall, you said that you can move boot entries up and down, so that might be all you need to do right this minute.

                                                brent I don't know how to get rid of all the boot entries. Found no info for my AMI V.25.2 and my MSI-7817.
                                                What my weird bios DOES have, however, is this UEFI Shell Teminal. It's a terminal. I have no idea what language/commands to use it in. But I bet that's the key. Or is it?

                                                Sounds like it might be.

                                                brent Will research more.

                                                That's good idea, but be careful before you start hacking away. As you said in an earlier comment, you are probably okay if the Windows Boot Manager and the Linux Boot Manager are the first two entries.

                                                By the way, I ran across this little squib about how to unlock AMI BIOS hidden settings. That might be easier than using the shell, if it works. I have no idea if it will work. Maybe it will unhide "delete boot entry".

                                                        Brucehankins Thanks

                                                        brent It runs in the terminal. You can find a short tutorial on basic commands here. I have not used it, because I have only two boot entries (Windows Boot Manager and Windows Boot Manager) and want to keep both, but I understand the syntac enough to know that you are going to have to be very careful to get the boot number dead right.

                                                        From the tutorial:

                                                        1. Deleting Boot Entry

                                                        Let’s say you have installed multiple Linux distributions on a hard disk so you have multiple boot entries just like the above screenshot. And now you deleted a Linux distro but the boot entry is still there. To remove the respective boot entry, run:

                                                        sudo efibootmgr -b <bootnum> -B

                                                        For example,

                                                        sudo efibootmgr -b 0014 -B

                                                        -b option specify the boot number. -B option delete that boot number.

                                                        My advice: See if you can get into your BIOS far enough to find a tool to delete inactive boot entries, and see if that is something you want to use. If you can't get in or think that the BIOS method is more than you want to take on, then install and try efibootmgr.