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Suddenly cant boot into windows 10 anymore.

Joined
Feb 11, 2009
Messages
5,894 (0.98/day)
System Name Cyberline
Processor Intel Core i7 2600k -> 12600k
Motherboard Asus P8P67 LE Rev 3.0 -> Gigabyte Z690 Auros Elite DDR4
Cooling Tuniq Tower 120 -> Custom Watercoolingloop
Memory Corsair (4x2) 8gb 1600mhz -> Crucial (8x2) 16gb 3600mhz
Video Card(s) AMD RX480 -> RX7800XT
Storage Samsung 750 Evo 250gb SSD + WD 1tb x 2 + WD 2tb -> 2tb MVMe SSD
Display(s) Philips 32inch LPF5605H (television) -> Dell S3220DGF
Case antec 600 -> Thermaltake Tenor HTCP case
Audio Device(s) Focusrite 2i4 (USB)
Power Supply Seasonic 620watt 80+ Platinum
Mouse Elecom EX-G
Keyboard Rapoo V700
Software Windows 10 Pro 64bit
Ok so my PC crashed twice in quick succession so I wanted to test something and tried to restart into "Safe Mode".

After that I got this very same message:
https://i0.wp.com/neosmart.net/wiki/wp-content/uploads/sites/5/2015/02/reboot-and-select-proper-boot-device.jpg?fit=980,250&ssl=1

"Reboot and select proper boot device".

Now there is a lot about this on the interwebz and youtubez but its getting tiring to sift through it all.


Here is where I stand so far:

Windows 10 is installed on a fairly new Samsung 750 Evo SSD (250gb).
I recon maybe a year, year and a half old.

The boot order is fine, this is a much suggested fix but it isnt my problem.
My Asus mobo does recognize the disk correctly and even the specific boot partition (I tried swapping the boot order every way).

I made a Windows 10 media usb stick thing and tried to use the build in "fix start up" but that almost immidiatly says it cant find any problems.
I did a chkdsk and a SFC Scannow using the CMD menu on the usb stick, which came up empty, no problems, and trying to just boot again after that did not help/fix it.

I hooked up an old HDD from a laptop to the pc instead of the SSD and that booted up just fine into windows 7.
With that I hooked up the windows 10 SSD alongside it and I can check the files which seemingly are all there and intact though I dont know what I would need to look for anyway that could cause this boot issue.
But for example my Desktop saved files were all there and in perfectly fine condition.

I finally tried something I wanted to avoid, reinstalling windows but keeping the files using that usb media stick but it told me that it could not do it via that, in that menu or whatever.
(guess I need to do it when already booted into windows 10 or something? and why is that option even there if that doesnt work... maybe I can only do a fully clean delete everything reinstall?)


Aaanywho, that is where im at right now.
Anyone any clue on what I could do next?

Im kinda hesitant to completely reinstall windows 10 due to not knowing how that will play with my other HDD's that I normally have alongside it that contain most of my programmes and games.
 
Last edited:
bootrec /fixmbr
bootrec /fixboot
bootrec /RebuildBcd

Try these in a command prompt.
 
bootrec /fixmbr
bootrec /fixboot
bootrec /RebuildBcd

Try these in a command prompt.

ok so on the first it immediately says: the operation completed successfully.
on the second it says: access is denied.
because of that i did not try to do the 3rd yet.

EDIT: did try the 3rd now because it was shown in a different order on some other guide and that gave me this:
"successfully scanned windows installation"
"total identified windows installations: 1
1 C:\windows
add installation to boot list? Yes No All: Yes
The requested system device cannot be found.


So both dont work, now I found this guide here:
http://triplescomputers.com/blog/casestudies/repair-a-corrupted-efiuefi-boot-sector-and-bcd/

Which basically goes over these issues, but Im a little hesitant and mystified by the solution suggestions.
For one yes my SSD is GPT formatted.
It says that with diskpart I should see the system's partition, being usually around 500mb in size and with an ID of EFI.

Now when I used diskpart list volume I get this:
Volume 0E--DVD-Rom 0 BNo Media
Volume 1C-NTFSPartition231 GBHealthy
Volume 2--NTFSPartition854 MBHealthy
Volume 3--Fat32Partition100 MBHealthy Hidden
Volume 4DESD-USBFat32Removable 32 GBHealthy

Soooo is the system partition the 854 MB Volume 2 that doesnt have a letter assigned to it?
Nothing about EFI in there but its the closest (just) to 500MB.

Or is it the hidden Volume 3 at 100MB?

Next to that when I use diskpart and type List Disk it gives me this:
Disk 0Status: OnlineSize: 232 GBFree: 451 MBDyn: - Gpt: *
Disk 1Status: OnlineSize: 32 GBFree: 219 MBDyn: - Gpt: -

The first is the SSD the second is the USB stick I take it,
Why does it say only 451 MB free? or 219 MB on the other?


Anywho back to that guide linked earlier:
They talk of assigning a letter to the correct volume, the one with the EFI partition (which again idk which that is, it does not seem to say anywhere).
They then talk of formatting that on using: format N(example letter): /FS:FAT32.

Sooo is that safe? wont that delete stuff, reformating it?
And also I think mine is NTFS, depending one which they mean, the 100mb or the 854MB one.
Wont that cause issues? do I have to format it with FAT32?
Or could I just as well fill in: format N: /FS:NTFS ?
 
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Probably a W10 update borked it.

I'd pull the files you want and then if possible secure erase the drive and put win 7 on it.
 
Well did this entire thing, which threw up the always needed, not anticipated hurdles, but at the end, nothing changed.
Still get access denied and the requested system device cannot be found with the boot rec stuff.

Step 3. Select Command Prompt.

Step 4. Type diskpart and press Enter key.

Step 5. Type list disk and press Enter. Now pay attention to the disk number and identify which one is the boot disk. Usually, it is Disk 0; if not, find the disk number in your own case and remember to type the correct one in the following relevant steps.

Step 6. Type select disk 0 and press Enter.

Step 7. Type list volume and press Enter. Now pay attention to the volume number of the EFI partition.

Step 8. Type select volume N and press Enter. Also, type the one in your own case instead of N.

Step 9. Type assign letter=N: and press Enter. N: can be replaced by any drive letter that is not taken by any partition. Remember which drive letter you assign here for it is rather useful in the rest steps.

Step 10. Type exit and press Enter to leave diskpart.

Step 11. Now type N: (the drive lettered you just assigned) and hit Enter.

Step 12. Type format N: /FS:FAT32 and hit Enter.

Step 13. Type bcdboot C:\windows /s N: /f UEFI and hit Enter.

Now repeat the process of running the bootrec /fixboot command

So yeah, what now?
anyone any idea how I can reinstall windows 10 without losing my files?
Thats like my main problem, idk what will happen to... well everything I have installed on other disks if I just reinstall windows cleanly.
 
Last edited:
It happened to me a few months ago and after I tried all those solutions and nothing worked I installed a fresh w10 v1903. I hope it works better for you. :toast:
 
Is it a MSI X99 HEDT MB if so it has an issue with microcode patch, win 1803 to 1809 update borked mine in similar fashion. Went to MSI site to get new bios and it fixed my boot issue.
 
Well did this entire thing, which through up the always needed not anticipated hurdles, but at the end, nothing changed.
Still get access denied and the requested system device cannot be found with the boot rec stuff.

Step 3. Select Command Prompt.

Step 4. Type diskpart and press Enter key.

Step 5. Type list disk and press Enter. Now pay attention to the disk number and identify which one is the boot disk. Usually, it is Disk 0; if not, find the disk number in your own case and remember to type the correct one in the following relevant steps.

Step 6. Type select disk 0 and press Enter.

Step 7. Type list volume and press Enter. Now pay attention to the volume number of the EFI partition.

Step 8. Type select volume N and press Enter. Also, type the one in your own case instead of N.

Step 9. Type assign letter=N: and press Enter. N: can be replaced by any drive letter that is not taken by any partition. Remember which drive letter you assign here for it is rather useful in the rest steps.

Step 10. Type exit and press Enter to leave diskpart.

Step 11. Now type N: (the drive lettered you just assigned) and hit Enter.

Step 12. Type format N: /FS:FAT32 and hit Enter.

Step 13. Type bcdboot C:\windows /s N: /f UEFI and hit Enter.

Now repeat the process of running the bootrec /fixboot command

So yeah, what now?
anyone any idea how I can reinstall windows 10 without losing my files?
Thats like my main problem, idk what will happen to... well everything I have installed on other disks if I just reinstall windows cleanly.


If you have a thumb drive or external drive that will fit all your stuff insert it and reboot to safe mode.

You can open notepad.exe by typing into the terminal and choose to open a file. That will give you an explorer window you can use to move things off with.
 
You have tried everything I would have so far. The reason I am posting is that I just have to thank the OP for being so elaborate with the details and investigative work before posting the question. Even the follow-up posts are amazing. It is very refreshing to see posts like these once in awhile. Keep up the good work TPU!
 
It happened to me a few months ago and after I tried all those solutions and nothing worked I installed a fresh w10 v1903. I hope it works better for you. :toast:

heh thanks, but currently it seems I am in the same boat :P

Is it a MSI X99 HEDT MB if so it has an issue with microcode patch, win 1803 to 1809 update borked mine in similar fashion. Went to MSI site to get new bios and it fixed my boot issue.

No i have an Asus P67 something or another, older mobo, but thanks, interesting to know how a bios and a windows update could mess up.

If you have a thumb drive or external drive that will fit all your stuff insert it and reboot to safe mode.

You can open notepad.exe by typing into the terminal and choose to open a file. That will give you an explorer window you can use to move things off with.

well I put the problem SSD windows 10 as an extra disk next to my working older laptop HDD running windows 7, so I have access to everything and can back it up.
Its just really painful to think about everything I would want to back up, heck accounts that I would all need to re-log in to, browser tabs I had open.
I just thought of backing up my Warframe (videogame) keybindings file just so I dont have to do all that again.
So that makes me, well hesitant to do a clean reinstall in the first place.

You have tried everything I would have so far. The reason I am posting is that I just have to thank the OP for being so elaborate with the details and investigative work before posting the question. Even the follow-up posts are amazing. It is very refreshing to see posts like these once in awhile. Keep up the good work TPU!

Thanks for the support ;)



Right so after all of that, final question.
Does anyone know of a way to reinstall windows without losing the files on it, without being able to boot into windows.
I have the SSD with windows 10 installed as an disk that I can hook up as an extra disk in another system.
Can I reinstall windows on that SSD while keeping the files that way?

I have a media creation usb, which will let me reinstall windows, but wont let me keep my files.
 
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