[Solved] Windows Cannot Boot: GPT Partitions Missing Boot & System Flags

[aw1983]

I'm sorry for asking for help, but I'm really desperate right now.

For days I've been trying to boot into my Windows (8.1 Pro) but I always fail because my system will never boot into Windows login screen. I can see Windows logo and the spinning dots, but before I can see the login screen, I get black screen and my monitor turns off with its power LED blinking (similar to losing an input) and several seconds later the system reboots itself.

It started with this: I tried to install Windows 10 to a hard drive a few days ago, but the installation always failed after reboot, something about error and I had to restart the installation. I did the usual things regarding OS installation: before installing Windows 10, I unplugged all my drives, leaving only the drive I wanted to install Windows 10 to, set the Windows 10 USB as the boot drive and started the installation. The system files and features could be installed or copied without a problem, but the installation always failed after a reboot (the installation asked for a reboot after installing the system files). To cut the long story short, I decided to give up. I shut down the system, plugged all my drives back, removed the Windows 10 USB and set my Windows 8.1 Pro drive as the boot drive.

To my shock and frustration, my Windows 8.1 Pro could not boot to login screen anymore. I could see Windows logo and the spinning dots, but I couldn't see the login screen because the display always went blank/black, my monitor's power LED blinking (similar to losing an input) and several seconds later the system rebooted itself.

Things I've tried:

- Using my Windows 7, I can still accessing all data in the Windows 8.1 partition, meaning the partition is not corrupted.

- I did several chkdsk to check the W8.1 partition, but I never saw any error.

- I cannot boot into Safe Mode because there's always black screen before the login screen and the system will always reboot itself several seconds after the black screen occurs.

- I used diskpart to check everything and found out that in the Info section of my W8.1 drive, I could not see either Boot or System flag anymore.

- I tried to repair the BCD with bootrec, bcdedit and bcdboot to no avail. I renamed or deleted the old BCD in EFI\Microsoft\Boot folder in the EFI partition (100 MB FAT32) and rebuild the BCD to no avail.

- When I used bootrec /scanos, my Windows 8.1 installation is detected, and when I used bootrec /rebuildbcd, it asked me if I wanted to add my Windows installation to BCD, which I always did. But still, I cannot boot past login screen. I can't even see login screen anymore because the black screen kicks in and the system reboots itself before the login screen shows up.


Details about BCD:

1. I run Command Prompt from Troubleshoot in my Windows 8.1 installation media.

2. I use diskpart by entering:
- select disk 0 (my W8.1 drive)
- list volume
- select volume 5 (the EFI partition)
- assign letter=B:
- exit

3. Then cd /d B:\EFI\Microsoft\Boot, followed by bootrec /fixboot.

4. I either renamed or deleted the BCD with ren BCD BCD.bak or del BCD.

5. Worth mentioning, I enter bootrec /scanos and it finds my Windows 8.1 installation. I enter bootrec /rebuildbcd to rebuild the BCD and add my Windows 8.1 installation to it.

6. I enter bcdedit to check for everything. Both {bootmgr} and {default} are in the BCD.

Windows Boot Manager
--------------------
identifier {bootmgr}
device partition=\Device\HarddiskVolume6
path \EFI\Microsoft\Boot\bootmgfw.efi
description Windows Boot Manager
inherit {globalsettings}
default {default}
resumeobject {*characters*}
displayorder {current}
toolsdisplayorder {memdiag}
timeout 30

Windows Boot Loader
-------------------
identifier {default}
device partition=C:
path \Windows\system32\winload.efi
description Windows 8.1 Pro
inherit {bootloadersettings}
recoverysequence {*characters*}
allowedinmemorysettings 0x15000075
osdevice partition=C:
systemroot \Windows
resumeobject {*characters*}
nx OptIn
bootmenupolicy Standard

p.s. To be honest, I copied this BCD from a thread in SuperUser, but I replaced several parts such as identifier, device and description according to my own BCD. Just to give an idea how my BCD look like.

7. Inside the C:\Boot folder: BCD, a few BCD.LOG files, BOOTSTAT.DAT, memtest.exe and languages, fonts and resources folders.

8. There are bootmgr and bootnxt files in the root C:\ and the timestamp is 2018, not 2021.

9. The C:\Windows still have Boot folder intact, the folders and files in it don't have 2021 as timestamp.


Even with all of these, I still can't boot into my Windows 8.1. I really need the OS for work, and there are things I need and must do for work that are stored in the OS. I didn't and still don't try to reinstall the OS because I will lose many of my works. Not to mention the OS itself is still intact.

Honestly I haven't sleep for 2 days and my head and my chest are really painful right now. I'm using whatever stamina I have left just to ask for help here. Please, if you have any idea to help me, I really want to hear about it. I really want to keep the OS considering the works. If it's just for gaming I just clean install everything, but there are unfinished works that I really need and I'm really desperate to make this OS boot again. Please, if you know something, please let me know and help me. Maybe to set/restore the boot and system flag again? The OS partition used to have the Boot flag and the EFI the System flag.

I think I need to lay down for a while. I don't feel so good right. I'm so sorry if my explanation is gibberish and I sound so pathetic. I really need your help in this.

Thanks so much in advance for any help.

 

[nuggdoctor]

This isnt my area but maybe someone that follows me or sees that i commented on it will be able to help you. OS issues is not my strongsuit. I hate installing them and when it comes to the older versions I dont bother keeping up with them all. sorry.

 

[aw1983]

Thanks for replying. It's fine though. I managed to boot and login to my Windows 8.1 Pro just recently. My friend came over and restored the boot files with his Macrium drive. So simple... Just boot to the rescue media, tick a few boxes, proceed and... done! My Windows 8.1 Pro partition now has Boot flag again. Spent at least 2 days trying to get a result with bootrec, bcdboot and bcdedit to no avail. And here I thought Macrium was only for maintaining drives similar to those many tools with "Partition" in their names.

To anybody looking for a solution to OS cannot boot, problems with BCD, system cannot detect bootable drive and other similar problems, give Macrium a try. Look for Macrium Reflect and use it. Create a bootable rescue drive (the tool allows you to do that, or you can create a bootable ISO and use Rufus to create a bootable drive with Macrium Rescue ISO, up yours), boot your system with it and restore the boot files. It's in the top bar menu of Macrium but you will only see it if you boot to Macrium rescue drive. It's not available if you run the tool in Windows. I don't have a license for a more advanced version of the tool, just the free one, but my friend is a technician and he has a paid Macrium license for servers. He restored my Windows 8.1 Pro boot files which I assume went fubar because of that botched Windows 10 installation.

So glad and relieved that it's done. There are so many unfishined works here that I can't access or backup without login to Windows first.

 

[nuggdoctor]

Im glad you got that figured out. nothing worse than when your pc cant even boot up.