OS won't boot, OS not found, 0xc000000f

[TomWin7]

Hi,

Before upgrading to Windows 10 (update was downloaded and ready to upgrade) I wanted to clean (Disk Cleanup) and backup my current system. I made custom backup (selected My Documents/Pictures/etc. only for my user) successfully on D drive (Windows is on C, there are no other drives). Also made Disk Cleanup (with default checkboxes selected + delete temporary files and old update files). I also created new restore point.

After described actions Windows worked correctly and I decided to restart the system. After restart Windows couldn't boot any more.

I see Windows Boot Manager screen with the following information:

File: \Boot\BCD
Status: 0xc000000f
Info: An error occurred while attempting to read the boot configuration data.

I cannot go anywhere from there. No safe mode, no nothing.

I created bootable USB with the same OS version in order to use "Repair your computer" from there.

After entering System Recovery Options from the booted USB it shows "Windows found problems with your computer's startup options". View details says it will repair {bootmgr}.

Clicking "Repair and restart" leads to error "Failed to save startup options."

In System Recovery Options no OS is listed, but it is possible to click Next.

After clicking Next next dialog shows "Operating system: Unknown on (Unknown) Local Disk".
Startup Repair shows that it cannot fix the problem automatically. Details in Startup Repair show:
Problem signature 01 / 02 : 6.1.7600.16385
Problem signature 03: unknown
Problem signature 04: -1
Problem signature 07: NoOsInstalled
...

Root cause found:
--------------
No OS files found on disk.
Repair action: Partition table repair
Result: Failed. Error code = 0x3bc3

In command prompt I've tried to make to make Windows partition as the only active one (using diskpart) - didn't help. I noticed that partitions have different letters from what they had when the system was running normally (i.e. C (Windows) partition became D etc.).
I've also used "bootrec /rebuildbcd" command which failed because it couldn't find Windows installation. Message:
Successfully scanned Windows installations.
Total identified Windows installations: 0

"bootrec /fixboot" -> The operation completed successfully.
"bootrec /fixmbr" -> The operation completed successfully.

During repair process sometimes I encounter with error 0x80070002.

System Restore doesn't work because it cannot find Windows installation.

PC: Asus A55VM, i5 3210M, 6 (4+2)GB DDR3 1600Mhz RAM.
OS: Windows 7 Professional 64bit, SP1

Please let me know if you need additional information.
Any help will be appreciated.

 

[Hacb]

i'd say the best thing to do is re-install windows.

 

[TomWin7]

I still have some files on C partition that I'd like to save. I'll keep reinstalling as the last option.

 

[DarKnight]

I still have some files on C partition that I'd like to save. I'll keep reinstalling as the last option.

Reinstalling windows doesn't means that you'll lose any of those files,you can back them up on your D partition

 

[fuzzypete]

I have the same problem,I in installed Win 10 on a separate partition using a USB stick and when I reboote abd removed the USB stick it would not boot up and gave me the same message.
However if I put the USB stick in before booting it boots up normally.
I am stumped what to do now and hope someone has an answer