PC does not boot and Windows repair/installation not working

Hi All,
I am a newbee i this forum, living in Germany :) Since a few days I am facing a big issue with my PC.
The battery of the mainboard (Asus P8Z77) was empty and I changed it already, but nevertheless the PC does not boot. Most probably the reason for that is a reset of the BIOS setup / UEFI settings.

Original error message in Windows\System32\Logfiles\Srt was
"c:\efi\microsoft\boot\resources\custom\bootres.dll is damaged" (original message was in german language).

First I tried a classical Windows repair, which didn't work.
Then I found an article and created the efi partition new. Worked obviously, this issue is gone. But now I get an error during boot:
"Operating system couldn't be loaded because a critical system is missing or contains errors.
File: \\windows\system32\drivers\wd\WdBoot.sys"

Windows Recovery tools are not working, so I tried a re-installation of Windows. But this didn't work either. System tells me that the C-harddrive is an UEFI drive, which maybe is not supported. So obviously a BIOS setup 0setting still refers to "legacy" instead of "UEFI".

I already checked that in the Boot settings, but everything seems to be correct there.

Anybody an idea, which setting in the BIOS setup could have this impact?

SSD seems to work fine, via cmd I get access to all drives, folders, and files.

thanks in advance

What settings were set in the BIOS:
a) UEFI native
b) UEFI hybrid with CSM
c) Legacy

Was the iso made from the Microsoft or another website?

Was the iso for 1903 or an older version?

Were you able to make an unallocated drive (delete all partitions)?

Clean Install Windows 10

Hi zbook,
thanks for the quick reply. If have set the BIOS to UEFI native (first it was hybrid, but both options do not work).
Original installation is from microsoft. For re-installing I tried an image created with this PC. ISO must have been for an older version than 1903.
Via cmd I have full access to the drives, can define and change partitions and everything. So it seems not to be an issue with the disk.
In the meantime I found that the reported error code 0xc0000221 could be hardware related. Already checked RAM, but that seems to work fine. Maybe the mainboard has a problem (battery was empty, but that's unlikely).

btw: I already tried a clean install. That told me that my disk is UEFI formatted, but the hardware does not support that. (although I had the BIOS settings to UEFI and the machine was already running fine).

0xc0000221 could be a checksum error and therefore hardware related.

Regards


PS: my issue seems to be very similar to that post: Startup repair couldn''t repair my pc BSOD error code 0xc0000221

PPS: and I have to say that I am an experienced computer user - even working in this job. But this issue is really weird.

Thx, already checked that. All 3 files are there. And there is a subfolder named "wd" containing different versions of these files. Also copied the files from the subfolder to the drivers folder, but without success....
At the end seems to be kind of a checksum error.
Next things I will try:
- Update BIOS
- trying different RAM modules
- connecting another physical hard drive as C:

Thx again!!!

See if any option works to clean install windows 10 1903 using an iso from the Microsoft website:
UEFI native, UEFI hybrid with CSM, or Legacy.

https://www.microsoft.com/en-us/soft...load/windows10
Download Windows 10 ISO File
Create Bootable USB Flash Drive to Install Windows 10

Once Windows is installed convert to the desired BIOS and disk formats:
Convert MBR Disk to GPT Disk in Windows 10