How to add Windows 7 To The Boot Menu

[Immitem]

Hello there, I am not going to go into too much detail because there are a LOT OF DETAILS! But I had W10 installed on a computer with its COA sticker but I needed Windows 7. Due to a variety of issues I had to pull all of the hard-drives except the one I wanted to install W7 on. I finally got it installed after a lot of fiddling (due to W7 not having the drivers necessary to recognise the SAS/SATA controller among a litany of other things) and it would boot up just fine.

Now here is the trouble.

I added all of the hard-drives back in and whenever the computer boots up it simply shows a single Windows Boot Manager in the boot-options where it promptly boots to Windows 10. Disabling all boot options allows the computer to boot into Windows 7 after a slight delay. Can someone demystify the process whereby I add Windows 7 to the Windows 10 boot manager because I am aware that it does not work the other way around.


Thanks!

 

[SkyNetRising]

Can someone demystify the process whereby I add Windows 7 to the Windows 10 boot manager because I am aware that it does not work the other way around.

Boot from windows 7 installation media.
Go into command prompt and use command:

• bootrec /rebuildbcd

It should allow you adding windows 7 boot entry to windows 10 bootloader.
Sometimes it can't do it automatically (if there are multiple bootloader partitions).
Then use command:

• bcdboot c:\windows /s x:

(c: - windows 7 os partition, x: - bootloader partition)
You may need to assign drive letter to bootloader partition using diskpart, if it doesn't get assigned automatically. Also windows 7 partition might have a different drive letter.

If you have problems identifying correct drive letters in windows recovery environment, then post output of

• diskpart
  list volume
  list disk
  select disk 0
  list partition
  select disk 1
  list partition
  ..
  select disk n
  list partition

 

[Immitem]

I shall give it a go and let you know how it goes.

 

[Alabalcho]

You can also try EasyBCD to edit your boot menu, or use BIOS to select the boot drive.

 

[Immitem]

You can also try EasyBCD to edit your boot menu, or use BIOS to select the boot drive.

The problem is that EasyBCD has always been a little flaky for me and I would be running it on pretty non-standard hardware.

EDIT: Also, the BIOS only shows one O.S. boot source and I cannot boot from any of the hard-drives as a source like I can on a couple of consumer boards.

 

[Immitem]

Can someone demystify the process whereby I add Windows 7 to the Windows 10 boot manager because I am aware that it does not work the other way around.

Boot from windows 7 installation media.
Go into command prompt and use command:

• bootrec /rebuildbcd

It should allow you adding windows 7 boot entry to windows 10 bootloader.
Sometimes it can't do it automatically (if there are multiple bootloader partitions).
Then use command:

• bcdboot c:\windows /s x:

(c: - windows 7 os partition, x: - bootloader partition)
You may need to assign drive letter to bootloader partition using diskpart, if it doesn't get assigned automatically. Also windows 7 partition might have a different drive letter.

If you have problems identifying correct drive letters in windows recovery environment, then post output of

• diskpart
  list volume
  list disk
  select disk 0
  list partition
  select disk 1
  list partition
  ..
  select disk n
  list partition

Ran into a wee-bit of a problem. I was only able to get the Windows 7 installation medium to find any of the disks by loading the respective driver from a flashdrive when installing it. Neither the command prompt nor the recovery option from the installation menu can detect anything (even when loading the drivers on the latter). I can still boot into each one and out of the pale I can suddenly boot into Windows 7 just by selecting its hard drive from the bootmenu (when before it would give me a nebulous error then promptly load W10). Is there no way to achieve this after I boot into either of the O.S.s as they both see all hard-drives in computer-management and seem to recognise that something is installed on each.

 

[SkyNetRising]

If you can boot into windows 7, then use bcdboot command to add boot entry to windows 10 bootloader.
Assign drive letter x: to windows 10 bootloader partition before executing the command:

• bcdboot c:\windows /s x:

(c: - windows 7 os partition, x: - windows 10 bootloader)
Execute from elevated command prompt.

 

[Immitem]

If you can boot into windows 7, then use bcdboot command to add boot entry to windows 10 bootloader.
Assign drive letter x: to windows 10 bootloader partition before executing the command:

• bcdboot c:\windows /s x:

(c: - windows 7 os partition, x: - windows 10 bootloader)
Execute from elevated command prompt.

Well, things have gone to hell in a hand-basket. Everything performed smoothly but when I restarted Windows 10 could not boot up. I did a reset/re-installation from the troubleshooting menu and everything seemed OK but when I booted into Windows 7 through the boot list it started telling me that it needed to do a disk check, something about NTSF and stuff so I thought what could be the harm? It bricked W10 a second time!

ARGH!

W10 is not that important to me, I just wanted to keep it around just in case (as well as the fact that I might as well get some mileage out of the now useless W7 COA license on it) but I am just not tech savvy enough to figure out how all of these different components are playing/fighting together. If push comes to shove I am just going to make sure that all of the W7 boot files are on the right disk and format the other drive into oblivion.

 

[SkyNetRising]

When dual booting windows 7 and windows 10, there is a setting in BIOS, that can cause file system corruption.
It's "Fast boot" has to be turned off.

 

[Immitem]

When dual booting windows 7 and windows 10, there is a setting in BIOS, that can cause file system corruption.
It's "Fast boot" has to be turned off.

Oh, I made sure that was never turned on, in fact by default (when selecting reset to defaults in the BIOS) it is turned off.