Dual-Boot Win7/Win10 on seprt HDD's - Both HDD's detected, 7 wont boot

Megahertz07 · 06 Sep 2016

As your original Win 10 was installed as UEFI, you should have installed Win 7 also as UEFI, changing only BIOS settings to CSM (Compatible System Mode) and detaching the Win 10 1T drive before installing Win 7 on the other drive.
What happened is that Win 7 was installed on the second drive but the boot loader was installed on the Win 10 drive.
Try this:
- Backup your data on an external drive.
- From Win 10 disk manager, make the Win 7 drive, that is MBR, active.
- Shut down and detach Win 10 drive.
- Boot from the Win 7 installation disk and make a boot repair. See if you can boot from Win 7 HDD.
- Attach the Win 10 drive.
- On BIOS set the main win to boot from, Win 10 or Win 7.
- To boot from the other HDD, press F12 and select from the list.

ThrashZone · 06 Sep 2016

Hi,

It's a lot easier to clean install these days with the unofficial sp2
There are essentially 3 updates needed for a clean install of windows that will get you updated through April of 2016

KB3020369 & KB3172605 & KB3125574 all can be downloaded from the M$ catalog using internet explorer
Microsoft Update Catalog

https://blogs.technet.microsoft.com/...ows-7-and-8-1/
When manually installing updates you need to switch your update settings to Never check for updates and restart the machine first.

After restart you will need to ensure the built in windows update service is stopped and set to manual first too or it will conflict with the stand alone installer.

Dual-Boot Win7/Win10 on seprt HDD's - Both HDD's detected, 7 wont boot-service-stop-windows-update.jpg

Afterwards reset the windows updates service to what it was before and update settings to your preference and check for updates
Should be only 50 or so updates left to install.

I also have all three updates on my OneDrive too if you prefer it instead of the catalog
https://1drv.ms/f/s!AsjD7o6P3KLKj2TjShn8-SumV1rr

Jmarc · 08 Sep 2016

Megahertz07 said:

As your original Win 10 was installed as UEFI, you should have installed Win 7 also as UEFI, changing only BIOS settings to CSM (Compatible System Mode) and detaching the Win 10 1T drive before installing Win 7 on the other drive.
What happened is that Win 7 was installed on the second drive but the boot loader was installed on the Win 10 drive.
Try this:
- Backup your data on an external drive.
- From Win 10 disk manager, make the Win 7 drive, that is MBR, active.
- Shut down and detach Win 10 drive.
- Boot from the Win 7 installation disk and make a boot repair. See if you can boot from Win 7 HDD.
- Attach the Win 10 drive.
- On BIOS set the main win to boot from, Win 10 or Win 7.
- To boot from the other HDD, press F12 and select from the list.

Thanks guys.

Megahertz07, I have a Dell XPS8900, I can't install Win7 UEFI, I've tried.

My only options in BIOS for installation are UEFI or Legacy mode. Win 7 installed in UEFI will freeze at the logo screen

https://msdnshared.blob.core.windows...2_5FBD7F32.jpg

Megahertz07 · 09 Sep 2016

Is your Win 7 32 or 64 bits?
Win 7 32 can only boot on Legacy.
On BIOS, Under UEFI, don't you have an option CSM (Compatible System Mode)?

Jmarc · 10 Sep 2016

My Win 7 is 64b, but when I installed and tried to run it in UEFI it freezes at the logo screen.

In my BIOS, if I choose UEFI, no I do not have a CSM option, but maybe it's time to flash it.

ThrashZone · 10 Sep 2016

Hi,
Just use the upload image option in the reply editor or paperclip symbol.

You might also take some images of the bios settings.

Jmarc · 10 Sep 2016

Oh ok.

So, if I am able to run Win7 in UEFI why does it freeze at logo screen?

Do I need to change video settings, or am I only able to run Win7 in UEFI with the CSM option (which I don't have)?

ThrashZone · 10 Sep 2016

Hi,
Bad media/ Boot device not formatted properly/ hdd not formatted properly/ win-7 is blocked in bios by the manufacture/.... :)

Megahertz07 · 10 Sep 2016

Jmark, if win 7 was installed as Legacy it will only boot with BIOS set as Legacy. Also if win 7 was installed as UEFI it will only boot with BIOS set as UEFI.
You said on first post that you had Win 7 (installed as legacy) and Win 10 (suppose it was installed as UEFI).
My questions are: To run Win 7 how was the BIOS (Legacy or UEFI) and to run Win 10 how was the BIOS (Legacy or UEFI)?
On post 13 you wrote "Win 7 installed in UEFI will freeze at the logo screen".
- You mean that you have tried and did installed with UEFI and then it freezes when booting at the logo screen, or,
- You booted from the installation disk and it freezes at the logo screen?
You have also attached a link with the boot options. Can you take another picture with a higher resolution with UEFI selected? There is a kind of a label on each line and a kind of button (view?). Is it a button? What shows if you press it?
I suppose you disabled secure boot. Did you?