[SOLVED] Win 10 - inaccessible boot device

[Haole Boy]

Aloha everyone. Have a strange one here. Was at a customer doing a general service and found 144 reallocated sectors on the hard drive. Imaged the old hard drive using ddrescue, ended up with 2 blocks that could not be rescued (1 TB drive). Used ddrescue again to copy the image to the new hard drive, it finished with no problems. Machine booted up fine, ran sfc /scannow and chkdisk - everything was OK

I powered down last night and this morning I had to r&r the motherboard - someone else had replaced it at some point and the ethernet port was blocked by one the grounding tabs for the case. I did have to remove the hard drive to get to one of the motherboard screws, but everything went back together OK.

Now, when I try to boot it, I get the inaccessible boot device error. ??? Startup repair doesn't fix it. When I go through the Win 10 advanced options and get to the command prompt, I can do a 'dir' on the C:\ drive and it works, I can open notepad and save a file to the c: drive, so it's not like the hard drive has stopped working.

I'm guessing somehow the bcd stuff got messed up (don't know, or understand how, since it was working yesterday).

I tried the following sequence that I found in many places on how to remove the existing bcd and create a new one:

bcdedit /export c:\bcdbackup
attrib c:\boot\bcd bcd.old
ren c:\boot\bcd\ bcd.old
bootrec /rebuildbcd

My understanding is the the last command is supposed to show that it found a Windows installation to add to the bcd. But it shows the found as 0 (zero).

I'm attaching diskpart output. This is a gpt disk (from what I can see in diskpart) and I'm unsure if any of the partitiions should be marked as active. Or if a required partition is hidden when it should not be.

This is an HP Pavilion 500 pc running Windows 10 AU.

Any assistance would be greatly appreciated.

Harry Z

 

[labtech]

If removing the drive and connecting it to a Windows machine, do the volumes mount? Likely, a boot file may have gotten corrupt.

 

[GTP]

Removing the Mobo may have reset BIOS defaults? Have you had a look in there? Checked boot order etc?

 

[NviGate Systems]

I always backup the BCD then run:

bcdboot c:\windows /s b: /f ALL

This assumes that your recovery environment has drive C as Windows. You may also need to use diskpart to mount the boot partition.

Since this is EFI, you don't need active partitions.

In your included diskpart, your boot partition is SYSTEM, and you will want to assign it a drive letter while doing manual repairs.

 

[ComputerRepairTech]

r&r = repair and replace? i dunno what r&r means but did you try to toggle the ahci status to see if that had changed.

 

[Diggs]

I've mentioned it before and don't mean to sound like a broken record but I use Lazesoft (one-click) on broken Win10 boots (after imaging). It's never failed me yet and if it fixes one machine it's worth the price.

 

[Haole Boy]

If removing the drive and connecting it to a Windows machine, do the volumes mount? Likely, a boot file may have gotten corrupt.

I have not put it in another machine, but I can see, read and write to the drive in both the recovery environment and WinPE. I agree that it's some sort of boot file error, but can't figure out which file is bad or how to fix it.

Removing the Mobo may have reset BIOS defaults? Have you had a look in there? Checked boot order etc?

Tried reloading defaults - no change. Found an updated BIOS on the HP website. Pulled the newly installed drive, put in another drive and did a quickie install of Win 10. Ran the BIOS update. Reinstalled the (new) customer drive - no change.

I always backup the BCD then run:

bcdboot c:\windows /s b: /f ALL

Did this, and found that the C:\boot\bcd file was not updated, but the bcd file in the "System" partiion was updated. Is this normal, or should the bcd in C:\boot be updated too? (Actually, should it have been created, I had renamed the existing bcd file as a backup.)

r&r = repair and replace? i dunno what r&r means but did you try to toggle the ahci status to see if that had changed.

r&r = remove and replace. And in this instance the "remove" was to just unscrew all the mounting screws so I can move the motherboard towards the front of the machine to enable me to bend the grounding tab that was blocking the ethernet port out of the way.

I've mentioned it before and don't mean to sound like a broken record but I use Lazesoft (one-click) on broken Win10 boots (after imaging). It's never failed me yet and if it fixes one machine it's worth the price.

Bought it, doesn't work. Just says there was an error updateing the bcd. Sent email to their tech support. We'll see how long it takes to get a reply...

Mahalo to all who replied. Any additional suggestions are greatly appreciated.

Harry Z.

 

[NviGate Systems]

Any BCD entry in C can be ignored, EFI is unable to read NTFS until the BCD and loader is loaded into ram.

 

[Haole Boy]

Any BCD entry in C can be ignored, EFI is unable to read NTFS until the BCD and loader is loaded into ram.

Thanx!

 

[Haole Boy]

Here's the latest.....

So, after doing the bcdboot command mentioned above, tried to reboot the machine. No video at all - no bios splash screen, nothing. Tried a couple of video cards I have just for this purpose. Nothing. Tested the power supply, it showed an error, so replaced it. Now I have video!

Boot failed with a 0xc00000001 error and gave me an option to retry. Got the boot options screen and selected Safe mode with networking. System came up!!! Rebooted normally, and the system came up!!! So, I have no idea why it's working now (since I got the 0xc0000001 error the first time I tried to boot, but I'll take it). Doing updates right now... will try to reboot in a little while.

If anyone has any insights on this strange scenario it would be greatly appreciated.

Mahalo,

Harry Z

 

[Rocco]

If the power supply was not working, it could send all kinds of errors to the motherboard. I have had some of the weirdest errors due to a faulty PS. Or one on its final legs. If I am troubleshooting a pc, before I replace any other parts, I always test it now.

 

[Haole Boy]

OK. I'm going to call this one "solved" and blame it on the power supply.

Mahalo to everyone who assisted

Harry Z.