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Something I’ve always done over the years is run weekly 100% mirror image bootable backup clones of the C-drive in my ThinkPad laptops…using spare USB cable connected SSD hard drives. [ connect the drive, run ‘Acronis True Image’ cloning software that I use, done ]
From time to time I’d boot the laptop from a USB backup drive, always worked perfectly…but mostly I’d just make the weekly backups for peace of mind in case the C-drive should ever fail.
But discovered a pesky little problem as I’ve been setting up a new ThinkPad P52 to replace my older P51. After I finished setting up the new P52 C-drive, I cloned it to a USB attached hard drive like I’ve done on the P51 a couple hundred times…and then just to be sure it worked, tried to boot the P52 back from the cloned USB attached drive.
Failed…blue screen error message: “Inaccessible Boot Device”.
TROUBLE SHOOTING SUMMARY SO FAR:
The P52 ThinkPad boots up normally / works perfectly from its internal C-drive.
All USB flash drives and/or USB cabled hard drives that I plug in all operate normally.
The P52 laptop sees them all, adds them to the list of other drives in the laptop (c, d, e, f, etc.).
I can read/ write to them business as usual, click open / look at content inside normally.
My cloning software works like always because I’ve taken cloned copies and physically installed them inside the laptop as the internal C-drive and the laptop comes right up normally / works perfectly, etc. I simply cannot BOOT FROM a USB connected clone any longer.
I’ve spent hours over a few days Internet searching, trying this, trying that, no help.
I’ve tried different SSD hard drives, different cables, different USB ports, no help.
Ran a few check-disk kinds of scans and the SSD’s are rock solid as always.
Ensured all Lenovo ThinkPad updates are downloaded and installed.
Ensured all Windows updates are downloaded and installed.
Then started trying the approach of uninstalling Windows updates one at a time but it’s very time consuming and several of the "security related Win updates" wouldn’t let me uninstall them.
So I decided to go back and ensure everything sill worked OK on the original P51, and to my surprise it fails the same way. Been quite a while since I actually did a USB Boot on the original P51 so I assume something must have changed during the past several months and I’m thinking the Win 10 Pro software is the common denominator.
Thought I’d check here with the Brain Trust and see if anyone might know of a specific Win 10 related finding / fix for this situation…thanks a lot in advance.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Hi,
I've still got a bit of curiosity as to what is going on with the error message.. That tool is nice, but I would rather be able to fix it without any 3rd party tools.. Especially ones that need installed.. Sometimes though, the fix is so lengthy or complicated, it is far easier to use a tool created for that purpose..
Hi,
I am not finding anything else useful concerning your error.. A lot of stuff about "Inaccessible Boot Device", but almost zero concerning your specific circumstances... Even then, I have used a good number of the fixes for other reasons in the past which worked, but do nothing for this issue..
All of the stuff I read is about fixing some type of boot error... which you have... but they are not working because of the USB connection making the drive an invalid boot device.. Basically by design..
Good luck with that Security System..
12/13/20 - UPDATE on WinToUSB
My full C-Drive backup routine has settled in to making my Acronis C-Drive clones to a USB connected SSD as usual…but then also using the WinToUSB software on my C-Drive to reach to out to the USB SSD drive to tweak it so it’ll do a USB connected Boot-up the same as if it was my Internal C-Drive…works great.
After a few days, the thought occurred to me…wondered if I actually had to physically replace my internal C-Drive with a USB SSD cloned drive, would the WinToUSB tweak on the USB SSD clone keep it from working as a physical internal C-Drive.
So I ran an Acronis clone FROM a USB connected WinToUSB SSD Drive TO the internal C-Drive, then booted the laptop up normally from the newly cloned C-Drive, and it worked perfectly / normally…so that was good to know.
AND…then to my surprise…ever since I cloned a bootable USB SSD to the C-Drive, the C-Drive now also has the little Windows tweak on it from the USB SSD copy.
Subsequently, now every routine clone I make from the C-Drive to a USB connected SSD automatically makes the USB SSD bootable, without having to take the extra separate step of adding the WinToUSB tweak to it.
Hi,
That sounds like it would make things a lot easier.. I knew the external SSD would boot if hooked up internally, but had not checked to see what it would happen if it were then cloned..
I've been wondering all along if something like that may have happened in the past and was the reason you were able to boot from The USB SSD without any messing around.. It was either that of you were never actually booting from the USB SSD and were being redirected by the Bios to the internal drive..
Don't know...but as I've said, I assumed it was booting from the USB as there were never any errors, the drives were visible in the "This PC" listing, etc.
What does continue to amaze me through all this is:
The little free WinToUSB feature you found seems so simple and fast...(1-2 seconds more than a screen-blink)...why in the world hasn't Microsoft gone ahead and tweaked that feature into their software is beyond me...especially given that they are already in that same arena by doing it for USB Flash Drives.
At any rate, hat's off to you for finding / sharing "WinToUSB".....I learned a lot and now can "see & know" I have 100% Bootable USB SSD drives at the ready with no more effort than running my Acronis clones like I always did.
