Windows 10: Startup repair wont play after linux grub messup.

Hello to the forum with a problem of my own creation. Followed this tutorial ... Boot to Advanced Startup Options in Windows 10 But Troubleshoot/advanced/startup repair functions but cannot actually do any repair. Reason for invoking = w10p on primary internal nvme drive ... still capable of booting from Grub after a "wrong" linux install to an external ssd. I can get a grub bootloader IF the external drive is connected and from there choose windows and all is fine. Did not intend this to be the method (I note others trying this type of install complaining that Calamares installer makes wrong decisions). The linux install fails to boot as well - but dont care as it was a test - and it is on an external so can just drop the lot and start again. But cannot drop it yet as it seems to be needed to get access to the windows boot. I have tried variations from bios boot order and the normal windows boot location will not boot directly (nor will the linux external either). So wanted to repair the existing windows bootloader - hence following Advanced StartUp ... SetUp Repair. But did not succeed. 20H2 up-to-date and currently functioning as expected ... only the bootloader seems to be the problem. Anyone got a big fat Linux swatter ?

:)

 

Repair Grub booting, there is probably a chance to?






Hej Andry, välkommen till Ten Forums.

Ten Forums är en engelskt sajt, alla posten ska vara på engelska eller innehålla en engelsk översättning. Med det sagt, jag föreslår att du tar det här upp på Ubuntu / Linux forum, för det verkar vara en Grub / Linux problem.







Hello Andry, welcome to the Ten Forums.

Ten Forums is an English site, all the posts must be in English or contain an English translation. Having said that, I suggest you take this up on Ubuntu / Linux forums, for it seems to be a Grub / Linux problem.

 

linux grub bootloader failed after win 10 updates


I tried:

grub rescue>set boot=(hd0,msdos6)
grub rescue>set prefix=(hd0,msdos6)/boot/grub
grub rescue>insmod normal
error: no such partition.
grub rescue>

ls
(hd0) (hd0,msdos1)
grub rescue>set boot=(hd0,msdos1)
grub rescue>set prefix=(hd0,msdos1)/boot/grub
grub rescue>insmod normal
error: unknown filesystem.
grub rescue>

grub rescue>set boot=(hd0)
grub rescue>set prefix=(hd0)/boot/grub
grub rescue>insmod normal
error: no such partition.
grub rescue>

My limited linux knowledge got me nowhere there.

Now downloading a 64 bit Windows 10 N iso through media creation tool to try a boot repair for Windows.

Burnt a disk, went to repair/Advanced Options/Command Prompt
Tried:

• bootrec /RebuildBcd
• bootrec /fixMbr
• bootrec /fixboot
• Exit

At Rebuild Bcd it only found Windows.old

 

Grub Rescue.

Hello Kaustubh,

Noting the details that you have provided.

Generally speaking, the most common reason for this error is due to a misconfigured bootloader file. While installing Ubuntu in Windows, a part of Grub lives in the Master Boot Record (MBR), while the other parts live in the Linux boot partition. That is
to say, although the Ubuntu partition is deleted, Grub is still in MBR. In addition, the active partition is not set correctly. As a result, on the startup of operating system Windows 10, you receive such an error of
no such partition grub rescue.

To resolve this, let us go ahead and try to run the automatic Startup Repair feature using the Windows installation media that you have. If you do not have the Windows 10 installation media, you can click on this

link to download it first. Afterwards, you can follow the steps below on how you can perform the Startup Repair:

• Boot your computer using the installation media by inserting the DVD or USB flash drive and restarting your computer.
• Once you see a message saying Press any key to boot from DVD, press
  Enter. (If you do not see this message, you might need to change the boot priority order in your computer’s
  BIOS settings to have the DVD as the first boot priority.)
  • Note: Modifying BIOS/complementary metal oxide semiconductor (CMOS) settings incorrectly can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee
    that any problems resulting from the configuring of
    BIOS/CMOS settings can be solved. Modifications of the settings are at your own risk.
• Once you see the Install Windows page, click
  Repair your computer
• On the Choose an option screen, select
  Troubleshoot.
• Click Advanced options.
• Click Startup Repair.

Once the repair is finished, you should be able to boot your computer as normal. However, if the issue persists, we recommend that you reset your computer. The link below would give you the steps on resetting your PC without having to lose your personal
files saved on your computer:

Recovery options in Windows 10

Update us with the result so we can further assist you.