Fix Inaccessible Boot Device error on Windows 10

Windows users who upgrade their systems to a new version of Windows, mostly on Windows 10, may run into into Inaccessible Boot Device error when they do so.
Windows 10 machines are upgraded more often than machines running previous versions of Windows. The main reason for that is that Microsoft is pumping out two new feature updates per year for the operating system.
Install errors may happen at any of those updates; usually when they are download and installed through Windows Update.
I ran into INACCESSIBLE_BOOT_DEVICE machine running a Windows 10 Insider Build. Windows would download the update through Windows Update, and start the installation.
The error may be thrown under other circumstances. You may get it when you reset the PC, or when you install Windows 10 on a machine.
The working on updates screen appeared, and the update seemed to process just fine for some time. Eventually however, Windows threw a green screen of death, tried again, another green screen of death, and started System Restore operations to restore the previous version of the operating system.
There is a big thread over on the Microsoft Answers forum about the issue. A lot of users who ran Windows Insider Build 16199 ran into the error when they tried to update.
While there has been no overall consensus on this particular issues, some users reported success after they have performed one or more of the operations listed below.
But first, lets take a quick look at what the error means actually.
According to Microsoft's own documentation, INACCESSIBLE_BOOT_DEVICE means the following:
This bug check indicates that the Microsoft Windows operating system has lost access to the system partition during startup.
This means, basically, that the Windows Update process somehow could not access the boot device anymore.
The error that Windows throws is unfortunately not very forthcoming, and there are quite a handful of possible explanations for the error. There is no single fits it all solution to overcome the error.
Fix Inaccessible Boot Device error on Windows 10
Solution 1: External devices
Windows Update may get confused with some of the extra hardware that is connected to the device during the upgrade. While this should not happen, users reported success after removing external hard drives or switching of LAN Booting.
If you don't require a drive during boot, or a setting that may interfere with boot, you may want to disconnect or disable it temporarily.
Solution 2: Hard Drive Damaged
While you may be able to run the current version of Windows 10 just fine, upgrades may not complete if the hard drive is damaged.
The easiest option to make sure that this is not the case is to run a scan for errors.
- Simply right-click on the drive in question, and select properties.
- Switch to the Tools tab.
- Hit the check button there.
Wait for the scanning to complete. If errors are found, Windows attempts to repair them.
Solution 3: Encryption
If you have encrypted the boot partition, you may run into issues with upgrades to new versions of Windows 10. If you use encryption, you may have run into a similar error before: The installation failed in the SAFE_OS phase..
The only resource that I know of that fixes the issue is to decrypt the drive, run the upgrade, and encrypt it again afterwards.
Not very pleasant, as it may take hours or even days to decrypt or encrypt the drive depending on its size, data, and the performance of the computer.
Solution 4: Security Software / Other Software
Again, something that is quite common, and causing issues during updates or installations in may occasions.
Windows 10 appears to be very sensitive when it comes to security software in general. Some users reported that the upgrade went through after removing security software, or other heavyweight software from the system (mostly software that would interfere with hard drives, or booting).
Solution 5: Install using ISO
This is more of a solution for feature updates on stable versions, and not so much one for Insider Build upgrades.
The instructions that we have posted for installing the Windows 10 Anniversary Update are still valid for newer versions of Windows 10.
Other solutions
- Report, and wait for a fix -- Another option that you have is to leave feedback, and wait for a fix to arrive. While you can do all sorts of things besides that, resetting the PC for instance, you will spend hours if not days trying to resolve an issue that you may not be able to resolve.
- Windows Update Troubleshooter -- Run the Windows Update Troubleshooter to make sure all Windows Update settings are configured correctly.
Now You: Did you run into the issue before? How did you fix it?


What mental age of reader are you targeting with the first sentence? 10?
Why not write an article on how to *avoid* upgrading from W10 to W11. Analogous to those like me who avoided upgrading from 7 to 10 for as long as possible.
If your paymaster Microsoft permits it, of course.
5. Rufus
6. Ventoy
PS. I hate reading these “SEO optimized” articles.
I used Rufus to create an installer for a 6th gen intel i5 that had MBR. It upgraded using Setup. No issues except for Win 11 always prompting me to replace my local account. Still using Win 10 Pro on all my other PCs to avoid the bullying.
bit pointless to upgrade for the sake of upgrading as you never know when you’ll get locked out because ms might suddenly not provide updates to unsupported systems.
ps…. time travelling?
written. Jan 15, 2023
Updated • Jan 13, 2023
This happens when you schedule a post in WordPress and update it before setting the publication date.
Anyone willing to downgrade to this awful OS must like inflicting themselves with harm.
I have become convinced now that anybody who has no qualms with using Windows 11/10 must fit into one of the following brackets:
1) Too young to remember a time before W10 and W11 (doesn’t know better)
2) Wants to play the latest games on their PC above anything else (or deeply needs some software which already dropped W7 support)
3) Doesn’t know too much about how computers work, worried that they’d be absolutely lost and in trouble without the “”latest security””
4) Microsoft apologist that tries to justify that the latest “features” and “changes” are actually a good thing, that improve Windows
5) Uses their computer to do a bare minimum of like 3 different things, browse web, check emails, etc, so really doesn’t fuss
Obviously that doesn’t cover everyone, there’s also the category that:
6) Actually liked W7 more than 10, and held out as long as possible before switching, begrudgingly uses 10 now
Have I missed any group off this list?
You have missed in this group just about any professional user that uses business software like CAD programs or ERP Programs which are 99% of all professional users from this list.
Linux doesn’t help anyone who is not a linux kid and apple is just a fancy facebook machine.
Microsoft has removed KB5029351 update
only from windows update though
KB5029351 is still available from the ms update catalog site
1. This update is labaled as PREVIEW if it causes issues to unintelligent people, then they shouldn’t have allowed Preview updates ot install.
2. I have installed it in a 11 years old computer, and no problems at all.
3. Making a big drama over a bluescreen for an updated labeled as preview is ridiculous.
This is probably another BS internet drama where people ran programs and scripts that modified the registry until they broke Windows, just for removing stuff that they weren’t even using just for the sake of it.
Maybe people should stop playing geeks and actually either use Windows 10 or Windows 11, but don’t try to modify things just for the sake of it.
Sometimes removing or stopping things (like defender is a perfect example) only need intelligence, not scripts or 3rd party programs that might mess with windows.
Windows 11 was a pointless release, it was just created because some of the Windows team wanted to boost sales with some sort of new and improved Windows 10. Instead, Microsoft cannot support one version well let alone two.
Windows 11 is the worst ugly shame by Microsoft ever. They should release with every new W11 version a complete free version of Starallback inside just to make this sh** OS functionally again.
motherboard maker MSI has recently released a statement regarding the “unsupported processor” blue screen error for their boards using Intel 600/700 series chipsets & to avoid the KB5029351 Win11 update:
https://www.msi.com/news/detail/MSI-On–UNSUPPORTED-PROCESSOR–Error-Message-of-Windows-11-Update-KB5029351-Preview-142215
check out the following recent articles:
Neowin – Microsoft puts little blame on its Windows update after UNSUPPORTED PROCESSOR BSOD bug:
https://www.neowin.net/news/microsoft-puts-little-blame-on-its-windows-update-after-unsupported-processor-bsod-bug/
BleepingComputer – Microsoft blames ‘unsupported processor’ blue screens on OEM vendors:
https://www.bleepingcomputer.com/news/microsoft/microsoft-blames-unsupported-processor-blue-screens-on-oem-vendors/
While there may be changes or updates to the Windows 10 Store for Business and Education in the future, it is premature to conclude that it will be discontinued based solely on rumors.
My advice, I left win 15 years ago. Now I’m a happy linux user (linuxmint) but there is Centos, Fedora, Ubuntu depending on your needs.
motherboard maker MSI has recently released new BIOS/firmware updates for their Intel 600 & 700 series motherboards to fix the “UNSUPPORTED_PROCESSOR” problem (Sept. 6):
https://www.msi.com/news/detail/Updated-BIOS-fixes-Error-Message–UNSUPPORTED-PROCESSOR–caused-BSOD-on-MSI-s-Intel-700-and-600-Series-Motherboards-142277