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How can I create a 2 hard-drive dual boot system with Windows 8 and Win 7 64bit in UEFI secure mode? I want to be able to choose which hard-drive with F12 (like with non-UEFI systems). Will I see both hard-drives and Operating Systems with F12? Will I have to go in and out of Legacy Mode (i.e. will Win 7 require it and Win 8 installed with UEFI not)? What problems can I expect? This has to be done with Secure mode because Win 8 is installed that way currently and does not mix well with Legacy Mode. Has anyone successfully setup a dual-boot of Win 7 64bit on a 2nd hard-drive in Secure and got it to appear in the F12 boot selection screen?

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Windows does not support Secure Boot and it cannot be made to support (unlike Linux) – Ramhound Sep 26 '13 at 23:40
@Ramhound One of the largest features of Windows 8/8.1 is secure boot (before Linux) – Mark Lopez Sep 27 '13 at 12:55
@MarkLopez - What is your point? Linux can be configured to support Secure Boot its not a simple process and very few distros support it but in general it can be done. Windows 7 cannot be configured to support Secure Boot, the only way to boot to WIndows 7 on a UEFI system is with Secure Boot disabled. – Ramhound Sep 27 '13 at 12:58
@Ramhound I was commenting on your statement that Windows does not support Secure Boot. As a possible solution - many computers allow for backwards compatibility with the the old BIOS standard. Cyber could install Windows 8 in UEFI mode, and Windows 7 in BIOS mode. I have done this with Ubuntu and Windows 8. Although this does break the secure boot model, Windows 8 will still have access to the Fast Boot mode from UEFI. – Mark Lopez Sep 27 '13 at 13:11
@MarkLopez - I see your confusion. I forgot the "7" in my original comment. Although by using the context of the question itself one can guess I was talking about Windows 7 and not Windows 8 which is known to support Secure Boot – Ramhound Sep 27 '13 at 13:28

It's possible to boot Windows 8 with Secure Boot disabled. That's likely to be easier than trying to get Windows 7 to boot with Secure Boot enabled, so it's the approach I recommend. To do this, you need to go into your firmware's setup screens, locate the Secure Boot option, and disable it. Unfortunately, there's no standardization for how to do this, so I can't be more specific; you'll just have to peruse your options or check the documentation for your computer.

If you insist on using Secure Boot, it's conceivable that you could get the Windows 7 boot loader to boot with Secure Boot enabled by using the Linux shim or PreLoader programs, or possibly by using the Windows 8 bootmgfw.efi program to control the boot process. I've never tried doing either of these things, though, so I can't promise that either would work; I'm just providing two possible avenues for you to investigate. For more on shim and PreLoader, see my Web page on Linux Secure Boot options.

Ordinarily, when Windows 7 and 8 coexist on one computer in EFI mode, a single Windows boot loader (bootmgfw.efi, in the EFI\Microsoft\Boot directory on the ESP) controls access to both OSes. If you've got two hard disks, it might be possible to get each one installed on its own disk by installing each OS with the other's disk disconnected. You could then control the boot process with a boot manager like my rEFInd; but I've never tried this, so I can't promise it would work. The F12 key option to which you refer is the firmware's own boot manager. This might work, too, but it's likely to be less flexible than rEFInd. Also, some computers "helpfully" remove invalid boot loader entries from their built-in boot managers, so when you unplug with Windows 8 disk to install Windows 7, the Windows 8 boot loader may disappear from the firmware's built-in boot manager. It's possible to get it back by using an EFI shell's bcfg command or in other ways.

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Thanks! Nature of current problem is, I already have Win 8 installed and set up Secure. Don't want hassle of Win 8 reinstall in BIOS mode. Was hoping to just add 2nd SSD with Win 7 64, which I THOUGHT was compatible with Secure UEFI. Am MOST concerned that disconnecting win 8 HD, adding SSD with win 7 64 in Secure Mode may mess up recourse back to Win 8 Secure with original HD. Mixed Secure and Bios requires constant toggling HD and Secure Bios to switch, and whatever other gotchas. Resistant to 3rd party boot loaders, as when something goes wrong, it's a mess to untangle! – cyber Oct 1 '13 at 14:47
In addition to above ... Win 8 HD is GPT. Was going to let win 7 64 format as GPT if it will. If it won't, it will be MBR. Then no Secure option, right? Egad - all this used to be so easy! Am I back to reinstall win and then win 7 on 2 new HD formatted Mbr in Bios mode to get an easy F12 boot drive select like old days with no 3rd party boot manager (and not relying on Win 8 boot manager, which I also resist. Will this work FOR SURE! Any way to avoid the Win 8 BIOS reinstall on reformatted MBR disk to get what I want? – cyber Oct 1 '13 at 14:57
You're conflating UEFI and Secure Boot. The latter is just one optional feature of the former. You can disable Secure Boot on a computer that shipped with Windows 8 and it will continue to boot in EFI mode, just without Secure Boot active. – Rod Smith Oct 1 '13 at 23:35
Thanks Rod - you were correct, I was conflating. However, my impression and I believe experience was that on a GPT format with Secure enabled Win 8 install, when I disable secure it will not boot; seems to look for boot info in BIOS where there is none. So whenever I say above UEFI, I meant Secure Boot. Now I want to ADD a HD and install Win 7 64 on it such that I can F12 and simply choose HD from which to boot. Gotchas: How to format that Win 7 64 HD - GPT or MBR? How to install Win7 64 - Secure (preferred so not mixed secure/bios system) or do I need to go Bios install (and MBR?)? – cyber Oct 2 '13 at 13:58
I don't have Windows 8; however, I've seen many reports of people disabling Secure Boot on computers that shipped with Windows 8 and the computer continuing to boot Windows. If your experience is different, it's either very unusual or you've accidentally done something else, too. (One such "something else" is installing Linux; some GRUB configurations fail to chainload to Windows properly. Another is switching to a BIOS-mode boot.) As to the rest, see my original answer, but keep in mind that it's largely speculative. – Rod Smith Oct 2 '13 at 16:41

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