Hi,
Yes —
a sudden power loss can absolutely cause this, even in a VM. From your description, the most likely causes are:
- NTFS/file-system corruption inside the guest
- damaged BCD / boot files
- corrupted SYSTEM registry hive or related registry data
- less commonly, corruption in the virtual disk files on the host
The good news is that
this does not always require a reinstall.
First: protect the VM before trying repairs
Because the VM is already in a bad state, I strongly recommend:
- Power the VM off completely
- Make a copy of the entire VM folder on the host first
.vmx.vmdk- any split VMDK segments
.nvram
- If possible, work on the copy
That gives you a rollback point in case a repair attempt makes things worse.
Recommended repair order
1) Open Command Prompt in WinRE
From the Windows Recovery Environment:
Troubleshoot > Advanced options > Command Prompt
2) Identify the Windows and EFI/System partitions
Drive letters in WinRE are often different from normal boot.
Run:
Look for:
- the Windows partition: usually NTFS, largest partition, contains
Windows
- the EFI partition on UEFI systems: usually FAT32, often 100–300 MB
You can test a drive letter with:
Keep note of:
- Windows partition, for example:
C:
- EFI partition, for example:
S:
3) Check the file system first
Because the crash followed a power outage, this is the first real repair step.
If your Windows partition is
C:, run:
chkdsk C: /f
If it reports a lot of errors, or you suspect deeper corruption, run:
chkdsk C: /r
Notes:
/f repairs logical file-system errors/r is more thorough and takes much longer
If
chkdsk finds and fixes errors,
reboot once and test before doing more.
4) Repair offline system files
If the VM still will not boot, run offline SFC:
sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows
If your Windows folder is on another letter, adjust accordingly.
5) Rebuild boot files / BCD
This is usually more reliable than only using
bootrec.
If the VM uses UEFI
Assign a letter to the EFI partition if needed:
Code:
diskpart
list vol
select vol <EFI volume number>
assign letter=S
exit
Then rebuild boot files:
bcdboot C:\Windows /s S: /f UEFI
If the VM uses Legacy BIOS / MBR
Use:
bcdboot C:\Windows /f BIOS
Optional additional boot commands
After that, you can also try:
Code:
bootrec /scanos
bootrec /rebuildbcd
If
bootrec /fixboot returns
Access is denied, that is fairly common. In that case, rely on
bcdboot instead.
If “Bad System Config Info” still continues
This stop code is often tied to
registry corruption, especially the
SYSTEM hive.
6) Check whether RegBack contains usable registry backups
Run:
dir C:\Windows\System32\Config\RegBack
If the files there are
non-zero size, you may be able to restore them.
Back up current hives first
Code:
md C:\HiveBackup
copy C:\Windows\System32\Config\SYSTEM C:\HiveBackup\
copy C:\Windows\System32\Config\SOFTWARE C:\HiveBackup\
copy C:\Windows\System32\Config\SAM C:\HiveBackup\
copy C:\Windows\System32\Config\SECURITY C:\HiveBackup\
copy C:\Windows\System32\Config\DEFAULT C:\HiveBackup\
Then restore from RegBack
Code:
copy C:\Windows\System32\Config\RegBack\SYSTEM C:\Windows\System32\Config\
copy C:\Windows\System32\Config\RegBack\SOFTWARE C:\Windows\System32\Config\
copy C:\Windows\System32\Config\RegBack\SAM C:\Windows\System32\Config\
copy C:\Windows\System32\Config\RegBack\SECURITY C:\Windows\System32\Config\
copy C:\Windows\System32\Config\RegBack\DEFAULT C:\Windows\System32\Config\
Then reboot and test.
Important note
On newer Windows 10 builds,
RegBack is often empty or not automatically populated, so this method only works if those files actually contain data.
Useful diagnostics from WinRE
7) Read the Automatic Repair log
This can sometimes point to the exact failure:
type C:\Windows\System32\LogFiles\Srt\SrtTrail.txt
8) Inspect current BCD entries
bcdedit /enum all
If the Windows path or device entries are obviously wrong, that supports a BCD issue.
Additional recovery options before reinstalling
9) Try System Restore
If restore points exist:
Troubleshoot > Advanced options > System Restore
This is often one of the safest ways to recover from registry/boot damage.
10) Attach the VMDK to another working VM
If in-guest repair fails, a very practical VMware option is:
- create a second working Windows VM
- attach the broken VM’s VMDK as a secondary disk
- copy important data off it
- inspect the Windows folder
- run offline checks from the helper VM
This is often the best “no reinstall” path if the original guest will not recover cleanly.
Is this common after an unexpected shutdown in a VM?
Yes. It is not unique to VMware.
A VM is still running a real NTFS file system and real Windows registry hives inside a virtual disk. If power is cut during writes, you can get:
- dirty NTFS metadata
- incomplete registry hive writes
- damaged BCD
- pending update/servicing corruption
So this kind of failure is entirely plausible after a host power outage.
My suggested sequence for your case
If I were repairing this VM, I would do it in this exact order:
- Clone the VM folder
- Boot to WinRE Command Prompt
- Identify correct letters with
diskpart
- Run:
chkdsk C: /f
- Run:
sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows
- Rebuild boot files with:
bcdboot C:\Windows /s S: /f UEFI
or
bcdboot C:\Windows /f BIOS
- Reboot and test
- If still failing, inspect
SrtTrail.txt
- If still failing, check RegBack
- If still failing, mount the VMDK on another VM and recover data / continue offline repair
One caution specific to VMware
If multiple VMs or files were affected on the host after the outage, also check the
host disk and host file system. Sometimes the guest is only part of the problem, and the actual damage happened to the
.vmdk or host storage layer.
If you want, I can give you a
clean step-by-step command set for either UEFI or Legacy BIOS, depending on how this VMware guest was configured.
