Need help to fix the boot loader

windows 10 build 1607 OS Build 14393.2189

I managed to add windows 11 to my dual boot windows 10 and 7 and it was working fine but than I was trying different things to speed up windows 11 that was taking 3 minutes to boot so yesterday I clicked on something in the bios I think it was something to do with uefi and after restart the screen went booted into windows 7 but it was very low resolution with very large icons so I rebooted but than it would no longer boot into windows 7 it went into windows 11

So it looks like whatever I did it messed up the boot loader so I have no way to select anything it just goes directly into windows 11
I tried to use the easy bcd but it says I cant use it because I have it set for EFI I looked at the bios and it looks to me like it's all set for legacy unless I am missing something
so not sure if I can do anything else with the bios

I looked online for other ways to fix it but not much luck I tried the the bootrec command but that is not working or not available in windows 11
Not sure if there are any other commands I can use in windows 11
Finally I used diskpart to make the D drive active so I thought I could use easy bcd from there but I get the same error

Also now I am getting a message now about the bootloader missing when I try to boot and there is another windows boot manager that was added to the boot options I guess that was for this D drive that I am on now

I figured I better stop and ask some questions before I mess it up further
I don't have a windows 11 dvd so I can't use the repair option
I think I have a windows 7 dvd somewhere but I am hesitant to use it in case it overwrites something and makes windows 11 not usable
I could disconnect the windows 11 drive and than try to use the windows 7 to fix it and than add back the windows 11 so that would be another option available if nothing else works

Check the BIOS and see if you changed the default boot drive.

I forgot to mention after I rebooted after the first noticed that the resolution was low it never booted anymore but instead it was boot looping so it was just a black screen with an occasional flicker but no text or messages so I could not use the original boot drive in bios anymore I could only boot to windows 11 drive and now with this setting I made with diskpart there was a new windows boot loader in windows I can boot to windows 10

What is important here is boot error message which we can use.

Well it was saying at the top on a black screen Windows boot manager than below was saying windows failed to start and than to insert disk which I only have for windows 7 not 10 or 11
than below that it was showing File :\boot\bcd which I am not sure what it means

Basically I need to fix the boot sector I am just not sure how

I think I made it worse now I tried something else that did not work and now I have a different message It says an operating system wasn't found Disconnect any drives that don't contain any operating system
Press control+alt+del

I think I will disconnect the windows 11 since it's causing so much trouble

In this video, i will guide you on how to Rebuild the Boot Configuration Data (BCD) to fix some Windows startup issues.

Are you sure that originally the only thing you changed was a setting in the BIOS? We need to know everything you did before you had the boot problem so we can be of better help.

Another mystery I found is that for some reason the bios is not showing my hard drives it only show 1 out of the tree but when I use F11 to select one it shows all of them

Winuser said:

Are you sure that originally the only thing you changed was a setting in the BIOS? We need to know everything you did before you had the boot problem so we can be of better help.

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Yes it was something to do with UEFI I thought that may make it boot faster which it did not but there is no setting to go back to the original setting
I am thinking maybe to pull the cmos battery and maybe that will restore the original bios configuration

Make sure UEFI mode enable on BIOS and you can reset BIOS to factory default settings from within BIOS setup utility.

FreeBooter said:

In this video, i will guide you on how to Rebuild the Boot Configuration Data (BCD) to fix some Windows startup issues.

Click to expand...

Thanks I am aware of the bootrec command unfortunately it is not working in windows 10 or 11 it says it's an unrecognizable command access denied

MikeYants said:

Yes it was something to do with UEFI I thought that may make it boot faster which it did not but there is no setting to go back to the original setting
I am thinking maybe to pull the cmos battery and maybe that will restore the original bios configuration

Click to expand...

It's worth a try. If you post what motherboard or BIOS your computer is using, maybe someone will know what setting you changed.

Is the bootrec /RebuildBcd command giving you the error?

FreeBooter said:

Make sure UEFI mode enable on BIOS and you can reset BIOS to factory default settings from within BIOS setup utility

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Are you sure ? Because I believe that's why the easy bcd is not working and has some instructions to set it to legacy mode I believe that was the problem because windows 7 does not work with UEFI or at least that's what easy bcd is saying

MikeYants said:

Are you sure ? Because I believe that's why the easy bcd is not working and has some instructions to set it to legacy mode I believe that was the problem because windows 7 does not work with UEFI or at least that's what easy bcd is saying

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Windows 11 only works with UEFI mode.

FreeBooter said:

Windows 11 only works with UEFI mode.

Click to expand...

I understand that now but I did not know it's going to mess up the boot section

FreeBooter said:

Is the bootrec /RebuildBcd command giving you the error?

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Yes it's just the bootrec.exe part that is not recognized

MikeYants said:

Yes it's just the bootrec.exe part that is not recognized

Click to expand...

Are you executing the bootrec command from Windows 11 recovery environment?

I'm not expert on this, but did you happen to change to uefi from legacy bios in bios? Because if you do that, it won't see anything is installed at all. Just tested that the other day! It said something like - no operating system found/installed.