DL160 Gen 10 won't boot after system board repair

[DEMinSOCal]

Our DL160 Gen 10 server had a bad system board.  After a week, HP finally came out to repair it.  They replaced the system board and fired it up.  No boot. 

We have two SATA drives mirrored (RAID 1) using the on-board RAID controller.

When attempting to boot, the message that C:\Windows\System32\Config\System could not be found. 

Now, I did not setup this HP server originally, so I am not aware what the original UEFI and RAID controller settings were, but I am pretty sure they were RAID 1.  Plus, the controller did pick up the config on it's own, we didn't set the board.

I tried booting from a Windows 10 and Windows Server 2019 USB installer, hoping that from a command line, I can see the drive.  I can't.  The drives are not seen at all.  I assume because the Windows Server 2019 and Windows 10 do not include the HP RAID driver?

Another thing I tried was pulling one drive to see if the system would boot from the 2nd drive.  No boot.  So I put the 1st drive back in and now it's rebuilding the 1st drive at an incredibly slow rate, something like 0.5% after 6 hours.  At that rate, it'll be a month before it's done.  Also when I try to boot now, I get a stop code immediately -- 0xC000000e, device not found.

Any suggestion on how to recover this server.  I do have a current windows server backup.  Should I just reinstall fresh Windows Server 2019 and restore the backup or is there a quicker fix?

Thanks.

[AmRa]

You may try to rebuild the BCD (Boot Configuration Data) booting from the disc and and if still issue persists better to go for fresh OS installation.

Follow below instructions to rebuild the BCD booting from the disc:

a. Insert the installation DVD or USB and boot Windows 8 from it.

b. In the ‘Windows setup’ page select the ‘language to install’, 'Time and currency format’ and the ‘keyboard or input method’ and click on ‘next’.

c. Click on Repair your computer.

d. Click on Troubleshoot and then select Advanced Options.

e. Click on Command prompt and type the following commands and press Enter after each command:

Bootrec /fixmbr

Bootrec /fixboot

Bootrec /rebuildbcd

f. Restart the computer. Check if the issue persists.

[DEMinSOCal]

Thanks, AmRa, for the reply.  It's been about a week without a reply so I kept working on it and managed to get the server booting again.

Turns out the issue was a BCD issue.  The problem in fixing it is that the Windows Server 2019 disc does NOT have the disc driver for the HP Smart Array controller that is in the DL160.  WHY IS THAT? 

I did manage to "trick it" into loading the disc driver by downloading the driver from HP and extracting the files to my Windows Server 2019 USB installer.  Then I go through the steps like I am going to install Windows, up to the point of it looking for a drive to install to.  Of course there aren't any listed, but you can "Load Driver", so I browse to the driver I downloaded from HP.  It then sees the the RAID controller and drive!

Then, the trick is to BACK OUT of the install, all the way back to the beginning and choose "Repair computer".  It still has the disk driver loaded so it now sees the drives under command prompt!  BUT, alas, the BCD repair doesn't work because when I did the "Bootrec /rebuildbcd", it found my Windows installation but said it could not write to the drive (or something like that).  So that didn't work.

What DID WORK was this--in the past I have successfully fixed Windows boot isses (BCD related) using the free version of Macrium Reflex that creates a USB rescue drive.  I copied my HP disk drivers over to it so when it booted it would see the drives.  It did.  Then I performed a "Fix Windows boot issues" and voila!  IT WORKED!  Macrium was able to fix the BCD correct and the server booted fine.

Hopefully this helps someone in the future with BCD boot-related issues.