Windows 10: Disk Boot Failure, Attempting to restore EFI partition

Had a power loss and while I have my workstation on a battery backup I on impulse just killed the power to my PC instead of doing a proper shutdown. I had just completed a steam game installation at this point (Mafia III, not sure if this is relevant though).

Long story short, upon reboot, I experienced the following:





(Disk Boot Failure)

I loaded up a recovery USB and attempted a repair to no avail. From the command prompt I ran CHKDSK and DISKPART and got the following:







CHKDSK seems to indicate that my actual Win10 partition is still there but for some reason I don't see an EFI partition to boot into it. I'd like to see if restoring this partition gets me back my installation. I can go through a reinstall if need be but it will be an enormous pain and I will likely lose some important info as well.

How do I go about restoring my EFI partition?

For reference, the boot disk is a Samsung SSD 850; it's less than a couple years old and given that it was behind a battery when I lost power (not a surge, just accidentally flicked the wrong breaker) I'm surprised that it would fail in this manner.

Any advice would be much appreciated!

:)

 

Always booting from the wrong drive

The presence of the EFI System and MSR reserved partitions on the old install means it's a UEFI install to GPT disk. When you installed to the new disk it used the existing EFI System partition to Dual Boot so that when it was detached the new install cannot
boot. Had you not wanted the old install you should have unplugged it's drive during install. If you did anything else like installed the new Windows in Compatibility mode please advise.

Now if this were the Legacy BIOS with an MBR disk we could simply mark the new install's partition Active and run a few Startup Repairs or Rebuild the BCD to get it booting. But for UEFI there must be at least the EFI System partition to boot it. You
can create one by shrinking the Windows partition from the left by a minimum 500mb I'd recommend.

Then try either a bootable partition Manager or Diskpart from the Command Prompt of the booted Windows media to create the EFI System partition:

Create EFI System Partition in Easy Steps to Make Windows Bootable Again

Restore/Repair Deleted EFI Boot Partition in Windows 10/8/7 – EaseUS

If you can create it but it still won't boot then try a Startup Repair, or
Rebuild the BCD in Windows [10 to 20 Minutes] as a last resort to export
and rebuild which often works. **Note that the commands given to copy boot files must reference the EFI System partition and not Windows partition.

When doing these operations unplug all other physical drives. Plug the target Windows drive into SATA 1 which should be DISK 0.

 

System Image Backup restore behavior

Your Restore is still reliant on your System Boot EFI partition so make a boot Disk or USB to boot from your Bios if you cannot restore.

 

Hi, I'll assume you haven't yet discovered the value of disk imaging, which would have let you resolve this quickly without technical help. If so, I would recommend you start using this routinely when this is hopefully resolved.

1. First please download and create Kyhi's boot disk (DVD/USB disk) from the top of the Software and Apps section here.

Boot your PC from this, run Minitool Partition Manager and post a screenshot.

2. Using the same disk, run Macrium Reflect, and use its Fix Boot utility to attempt to resolve your boot problem

3. Assuming your Windows partition is intact, there is a way to rescue this using a Win 10 install disk and Macrium Reflect.
Try the above first.

 

Do you have a bootable DVD, CD or USB?
If you have a flash drive that you can format create a windows 10 bootable iso.
You have a custom computer and will likely need to modify the bios boot order to boot to the USB.
If there is an F key then you can boot to the USB without changing the boot order.

 

I am booting into my workstation using the Windows Recovery USB. I've already verified the boot order in my BIOS.

 

If your partition has disappeared - and without an answer to my previous post I will simply assume it has: you can

a. Create a disk image of your Windows partition (on an external disk) using e.g. Macrium Reflect (free).
b. Reinstall Win 10 on your system disk, erasing all existing partitions related to the Windows OS (keep any data ones)
c. Replace the newly created Windows partition by restoring yours from the image
d. Run Startup Repair from your Win 10 boot disk.

 

I would highly recommend you do as @dalchina suggested and boot the computer from Kyhi's Recovery Tools and see what the diagnostic tools on his recovery tools can do to fix the drive - you need to look specifically at partition recovery programs. From the screenshots the only partition you have on the drive is the 450MB Windows 10 recovery partition at the very end of the drive. You need to do more than create an EFI partition or "Fix Windows boot problems", you need to recover the Windows partition, if possible.

 

Apologies for the delay in this response, I will be running the steps in your previous post as well as this tonight - I decided to order (and had to wait for Amazon to deliver) a set of 16GB USB drives so I don't have to keep reflashing my pair of 8GB drives (one with Win10 recovery, one with Memtest) every time I need a new tool.

I'll post my results once I'm complete.

 

So I've attempted the steps @dalchina suggested but it seems that Macrium Reflect can no longer "see" my Windows partition on my SSD drive. I am able to run Power Disk Recovery (should I be using something different?) and find what looks to be my Windows partition but I'm not sure if this is the best way to go about restoring my original boot partition - if indeed this is even advisable.

Is there a better way to rescue my old Win10 boot partition?

I'm also considering RMA'ing my SSD drive but would like to run a diagnostic on the drive itself first...

Is there a utility on Kyhi's Recovery Disk (HDDScan?) that will do this?

 

Hi, regarding your partition structure- or what may be left of it- we're still waiting for a response to the following info (see #2)
- which is relevant as you say

1. First please download and create Kyhi's boot disk (DVD/USB disk) from the top of the Software and Apps section here.

Boot your PC from this, run Minitool Partition Manager and post a screenshot.
to post a screenshot please use the Insert Image icon above your post to the left of the video icon

2.

HD Tune, HDDScan
Note e.g. surface checks are available.

3. Lazesoft Recovery is on the disk too- Someone has used that successfully to effect a repair- I'm not familiar with it myself.Please feel free to explore it.

Note: most partition recovery programs are not free.

 

@dalchina: Thanks for your help & advice. The following are my results.

I have set up an RMA with Samsung and am inclined to get the SSD replaced once I have recovered everything possible - even if the drive appears healthy it doesn't seem like I should spontaneously lose my partition due to simple a power loss (no surge, I have the PC on a battery backup, I flipped the breakers and killed the power to the PC once I realized it was on battery)?

 

Well, as you know, there's nothing of interest shown by Minitool Partition Wizard apart from the absence of what would be of interest.

It seems you may have a chance of recovering your Windows partition.

Question is, would you be confident in it? (Ok, a half decent recovery program will give you an assessment of the validity of the data and the probability of successful recovery.

I also note all your disks are MBR rather than GPT - the more modern and robust file system. Any reason for that?
Whats the Difference Between GPT and MBR When Partitioning a Drive?

 

I don't know why they are MBR vs GPT - if I was forced to hazard a guess I'd say it had something to do with this installation being an old Win7 installation that I upgraded to Win10.

I guess I will just have to roll the dice with what I can pull from the disk using Kyhi's recovery tools then RMA the SSD with Samsung.

 

Some things to consider:

If you recover your Windows partition, you will need to do what I said in #5 to get Windows up and running again.
It is not enough simply to recover C: - there is at least one more partition you need, + the boot sector.
Depending on what you have installed, you may find a clean install the easiest and most reliable way tog go.

Your BIOS probably doesn't support UEFI- unless perhaps there is an upgrade that does. If so, GPT + UEFI would be an improvement.

When using a SSD, then using AHCI gives better performance, again, if supported by your BIOS.
Why do i need AHCI with a SSD Drive (Guide Here!) ... - Crucial Community

Recovering C: may at least allow you to recover data there, of course, if you don't already have backups.

Hopefully this experience will encourage you to start using disk imaging routinely - e.g. Macrium reflect (free) + its boot medium _ external storage for disk image sets. Disk images allow you to recover quite quickly without technical help even if your disk fails (new disk required!) or is inaccessible.