PC will no longer boot after failed installation version 1709

Sorry to hear of your problems.

Do you use disk imaging as we constantly recommend? If so you can restore a disk image of your previous build (E.g. Macrium Reflect (free) )

If not, recovery could be hard or impossible. However you may be lucky and find you can run system restore by booting from the Win 10 boot disk and using Advanced Startup options.

I believe it's also possible to uninstall an update from a non-booting system (providing it's not corrupted in some way of course).

Do you have full backups? (Or a disk image of your Windows partition?)

If not, you could boot from a boot disk such as Kyhi's available from the top of the software and Apps section here, and back up essential data.

Creating a bootable drive: .
Create Bootable USB Flash Drive to Install Windows 10 Installation Upgrade Tutorials

Creating a bootable USB drive.

with thanks to @NavyLCDR
To reliably make a bootable USB flash drive from an ISO file, do this:

Plug the drive into a USB port of a functioning Windows PC.

Open a command prompt.
Run diskpart.

Once diskpart is running, enter the following commands in sequence:

list disk
select disk #
- replace # with the actual disk number of the USB flash drive
clean
- this will erase the selected drive, make sure it is the USB flash drive!
create part pri
format fs=fat32 quick
active
exit
exit

Then mount your ISO file.
(By default you can simply right click the iso file, and click Mount. However, Mount will not be available if iso files have been associated with a different program).

Copy all the files and folders from the mounted ISO file to the USB flash drive.

(If stuck you can open the iso with 7-zip, a free program).

Discussion here:
Reinstall Windows 10 from DVD but no DVD drive
- includes content of flash drive.

OR use Rufus (freeware)
Create Bootable USB Flash Drive to Install Windows 10
See Option 2

Hi, if you have a bootable Win 10 drive (your post #1), then clearly you don't need to worry about the instructions for that.

However, if you wish to access your internal drive- for example to copy off/back up data- then Kyhi's boot disk is very useful. (It boots up as Win 10, with a range of utilities, so yo can of course use file explorer as usual).
You can use Rufus or those instructions to prepare the bootable disk, or burn the iso to a DVD if your PC has a DVD drive.

I understand your problem to be a failed upgrade to 1709 from an earlier build rather than as post #4.

Your options are very limited. I don't know of any way to reliably repair a non-booting Windows system in this case. Sure, there are
a. Startup Repair - (which I believe you've tried)
b. Macrium Reflect's Fixboot utility (available if you use Kyhi's boot disk)
but these are really not intended for this scenario, where we really don't know what state your system is in.

Try disconnecting any unnecessary peripherals and reboot.

You could post a screenshot of the partitions using Minitool Partition Wizard.

Search the forum for e.g.
fails to boot after upgrade
and similar for more clues.

E.g.
Search the forum for
automatic repair loop solved
(Your first post mentions this happens)

Check to see if your boot order has been changed
Windows 10 won't boot after using 'Upgrade only' option. Solved - Windows 10 Forums

Another idea, much more than you were thinking you'd need to do, but another choice. Obtain another drive, preferably an SSD. You can get a name brand 250G for around $100, probably less with holiday sales.

Install it as the only drive in you box, remove all other drives, use a bootable iso, either USB, or cd, and install W10 1709 on the drive. Once you're up and running, reinstall your existing drive with all your data back into the computer, then transfer anything you might want to the new drive running 1709. This gives the opportunity to weed out things that maybe you don't use anymore, or haven't used in a while. Or even better, leave everything alone on the old drive, delete the old W10 installation, and use it as a storage/backup drive. Then you'll have a backup/image on hand, Macrium is easy to set up to make backups automatically.

Just some random thoughts, you could clear several problems at once and have a clean install on a new SSD. Not sure what you have now, I have a Samsung SSD, cold boot to up and ready in around 30 seconds or so.

Good luck whatever you end up doing :)

P.S. IMO the reason for the 'clean' command is to ensure the USB is completely clean. USB's have been around for some time, and many of us have USB's that are still good but have had things on them at one time or another.

Hi.
Have a read of this thread (from post #13 on) - maybe it's a possibility for you:

No boot black screen, recovery c: access denied Solved - Page 2 - Windows 10 Forums

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