Windows 10 bootmgr no longer reading boot.ini

Hello! I've been testing the new bootmgr versions from Windows 10 images, Multiple Editions and Enterprise. The bootmgr from multi editions and enterprise have different checksums, and suprisingly none of them support boot.ini. The last known working edition is from windows 8.1.

Here's my issue of which i'd appreciate your guidance:

My USB drive is setup as: BOOTMGR -> BOOT.INI -> GRUB4DOS/POP

Now, In order for my VHDs to boot, I need bootmgr from windows 10. If I have bootmgr from 10, I no longer have boot.ini, and thus loose grub4dos and plop.

What could I do to have the best compatibility with VHDs and boot.ini?

Thank you!

You can boot other bootloader from 'bootmgr' by '.mbr' file

You can boot other bootloader from 'bootmgr' by '.mbr' file

So, bootmgr could boot grldr.mbr ? Or just rename grldr to grldr.mbr?

Have you set the "advanced boot options"?

https://www.tenforum...ndows-10-a.html

Wonko

You can boot via BCD to grldr

http://www.rmprepusb...os_from_bootmgr

@ Alexander Ceed

Just add grldr.mbr on same partition as bootmanager and using BootIce create a new BCD entry to load grldr.mbr, then assuming you already have grldr and menu.lst, thats all, (But you better update to a newer version).

Steve6375 recommended grub4dos-0.4.6a-2017-05-15 on this post:

http://reboot.pro/to...im/#entry203580

grub4dos downloads: http://grub4dos.chen...ries/downloads/

Thank you!

One more thing guys. The Windows 10 bootmgr no longer sees my VHDs now. I have one Windows 10 VHD and is not seeing the entry. All other entries are displayed expect this.

Here's a picture in bootice of the entry:

http://h.dropcanvas....5-24_210034.png

You need to specify the disk, partition and path to VHD

also you have winloade.exe - is it MBR booting and MBR BCD or UEFI BCD???

It's MBR boot, and MBR bcd. I double checked this. But the path is relative, it's on the same drive as bootmgr. On windows 8.1 this config works, as seen in the picture.

Same partition as bootmgr?? Was VHD in root last time?

Let me try to explain this another way: the config shown in the picture, works for bootmgr of Windows 8.1, exactly as it is. In windows 10 bootmgr it doesn't work and I don't know why.

@ Alexander Ceed

Just diferent code on Bootmanger and how it reads BCD (MS calls it improvement, not me).

Also you better check your partition lay out, 10 may have created new partitions at the very beginning of disk.

Then follow steve6375 advice:

 

You need to specify the disk, partition and path to VHD

This should work fine.

alacran

They changed something in bootmgr 10 that just isn't working with old bcd configs.

I'm using an HDD with two partitions, one active and bootable of 137GB NTFS and the other for data, also NTFS.

The disk MBR/PBR codes are as follows:

http://h.dropcanvas.com/emzwx/disk.png

http://h.dropcanvas....x/partition.png

I don't get it. Only the vhd entries are not listed, all the others like grub4dos or WIM are listed and working.

Maybe a problem with BootIce? Can you use BCDEdit to add in the VHD using Locate?

I was using an older version of bootice and that's why it didn't work. However, now it shows the entry but outputs the error 0xc00000bb BCD cannot find a required file.

I was using an older version of bootice and that's why it didn't work. However, now it shows the entry but outputs the error 0xc00000bb BCD cannot find a required file.

Try latest version from pauly's site and that should work as expected...

http://www.ipauly.co.../11/15/bootice/

I think the latest one is 1.3.4, from here http://bbs.wuyou.net...hread&tid=57675

Found the issue. I spent 6 hours for this crap . Apparently, the DVD folders for boot and EFI are not the same as the ones from a real installation of windows. Thus, I was missing the file bootvhd.dll and causded all VHD entries to be disabled. C:\windows\system32\boot did not help either. There are different timestamps and hashes on them.

Now everything works.

Booting from VHD in BIOS mode requires to add file bootvhd.dll from folder C:\Windows\Boot\PCAT to your Boot folder on USB.

This is automatically done when using bcdboot.exe in admin cmd window to add new boot entry for BCD file.

For support of BIOS and UEFI mode booting you need to do this for BCD files in boot and efi\microsoft\boot folder on FAT32 boot drive and  using mounted file VHD (located on NTFS partition).

BOOTICE does not add the required bootvhd.dll file .....

BOOTICE New entry in BCD for BIOS booting contains in Application Path wrongly winload.efi whereas it should be winload.exe for BIOS mode booting.