You did everything right. You bought a new SSD, cloned your old drive over, swapped it in — and instead of a faster computer, you got a blue screen that says INACCESSIBLE_BOOT_DEVICE.
Here's the good news: when this error shows up right after a clone, your data is almost always fine. The clone usually worked. Something small — a leftover drive, a missing boot file, a storage driver that didn't make the trip — is stopping Windows from finding itself on the new drive. Most of the cloned-drive boot failures we see at our Somerville bench come down to one of six causes, and several of them take five minutes to fix.
This guide covers the cloning-specific causes. If you're seeing this error and you didn't just clone or swap a drive, start with our full INACCESSIBLE_BOOT_DEVICE troubleshooting guide instead — the causes (and fixes) are different.
INACCESSIBLE_BOOT_DEVICE (stop code 0x0000007B) is different from errors like "Boot Device Not Found." Your BIOS did find the new SSD, and the Windows bootloader did start running. The crash happens a moment later, when Windows switches from the bootloader to its own storage drivers and suddenly can't access the partition it's booting from.
That distinction matters, because it tells you the clone mostly succeeded. The boot files ran. You're not starting over — you're fixing a handoff problem.
This is the number one cause, and the easiest fix. When you clone a disk, the copy gets the same disk signature as the original. Windows refuses to run two disks with identical signatures, so it forces one of them offline — and it doesn't always pick the one you'd want. The boot configuration can also end up pointing back at the old drive.
The fix: Shut down completely (hold the power button if you have to), physically disconnect or remove the original drive, and boot with only the new SSD connected. Don't reconnect the old drive until the new one boots cleanly on its own.
A working Windows drive isn't just the C: partition. On modern systems there's a small hidden EFI System Partition that holds the boot files, plus a recovery partition. Some cloning jobs copy the Windows partition but skip or mangle the EFI partition — or copy it but leave the boot configuration pointing at the old disk's identity.
The fix: Rebuild the boot files on the new drive (Step 4 below). It's a two-minute command-prompt job once you're booted into recovery.
Windows installed in the old Legacy/BIOS style needs an MBR-partitioned disk. Windows installed in modern UEFI mode needs a GPT disk. If your clone converted the partition style — or your BIOS settings changed boot modes during the swap — the firmware and the disk no longer speak the same language.
The fix: In your BIOS/UEFI settings, match the boot mode to your disk. If the old system booted Legacy/CSM, enable CSM. If it booted UEFI, make sure UEFI mode is on and "Windows Boot Manager" appears as a boot option.
Cloning from an old SATA hard drive to a fast NVMe SSD changes more than the connector — it changes which storage driver Windows needs at the very first moment of boot. If the NVMe driver wasn't flagged as boot-critical on the old installation, the kernel literally cannot see the drive it just booted from. Result: 0x7B.
Newer Intel laptops (11th-gen and later) add another wrinkle called VMD (Volume Management Device). If VMD is enabled in the BIOS but the cloned Windows installation never had the Intel RST/VMD driver, the drive is invisible to Windows even though the BIOS sees it fine.
The fix: One successful boot into Safe Mode usually solves the driver side of this — Safe Mode loads a minimal driver set and forces Windows to re-detect its boot storage. On Intel VMD machines, try toggling the VMD setting in the BIOS (usually under storage or advanced settings). One caution: only flip VMD if Windows won't boot — on a system that was installed with VMD on, turning it off breaks booting the other way.
It's common to reset the BIOS, update it, or "just check a few settings" during a drive swap. If the SATA mode flipped between AHCI and RAID/RST in the process, even a flawless clone will throw INACCESSIBLE_BOOT_DEVICE.
The fix: Set the SATA/storage mode back to exactly what it was before the swap. If you're not sure, AHCI is the most common setting on home machines.
If the old drive had bad sectors, your cloning software may have skipped, stalled, or silently copied corrupted system files. The clone looks complete but isn't.
The fix: A disk check can repair light filesystem damage (Step 5 below). But if the source drive was failing, stop and read the warning section before you do anything else — especially before re-cloning.
Work through these in order and try booting after each one.
Full shutdown. Disconnect the original drive entirely — not just unplugged from the boot order, physically disconnected. Boot. This alone fixes a surprising share of cloned-drive failures.
Confirm three things: the new drive (or "Windows Boot Manager") is first in the boot order, the SATA mode (AHCI/RAID) matches what it was before the swap, and the boot mode (UEFI vs. Legacy) matches your old setup.
Force the Windows recovery screen by interrupting the boot three times (power off as soon as the spinner appears), then choose Troubleshoot → Advanced options → Startup Settings → Restart, and press 4 for Safe Mode. If Safe Mode loads, simply restart normally — Windows re-registers its boot-critical storage drivers on that first successful boot, which is exactly what SATA-to-NVMe clones need. If your machine won't even reach the recovery screen, our guide on getting into Safe Mode when Windows won't boot covers the stubborn cases.
If recovery won't load from the drive, create a bootable Windows USB on another computer, boot from it, and choose Repair your computer → Troubleshoot → Command Prompt. Then:
For UEFI systems (most computers from the last decade):
diskpart
list volFind the small FAT32 volume (100–500 MB) on your new drive — that's the EFI partition. Then:
select vol X (replace X with that volume's number)
assign letter=S
exit
bcdboot C:\Windows /s S: /f UEFIFor older Legacy/MBR systems:
bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcdThis rewrites the boot configuration to point at the new drive's actual identity instead of the old disk's.
From that same command prompt:
chkdsk C: /fThis repairs filesystem damage from an imperfect clone. If chkdsk reports a long stream of errors, the clone copied corruption from the source — keep that in mind for the next section.
If nothing above works, re-clone — but this time select the entire disk, not just the C: partition, so the EFI and recovery partitions come along. Disconnect the original immediately after cloning and do the first boot with only the new drive installed.
Be honest about why you were cloning. If the answer is "the old drive was acting up" — slow, clicking, freezing, throwing SMART warnings — then every additional power-on of that drive, and especially every re-clone attempt, pushes it closer to total failure. Consumer cloning software hammers a weak drive with sustained reads it may not survive.
This is the point where a $120 DIY upgrade can turn into a four-figure recovery problem. If the source drive is unhealthy, stop cloning. We image failing drives with dedicated hardware that reads gently, retries intelligently, and works around damaged areas — then build you a clean, bootable copy from that image. You can read more about how our data recovery service handles failing drives, including hard drive recovery for mechanical drives that have started clicking or disappearing.
If you've worked through the steps and your clone still won't boot — or you'd rather not gamble with the only copy of your files — bring both drives to us. Our bench process for cloned-drive failures starts with a health check on the original drive, because the fix is completely different for a healthy source than a dying one. From there we rebuild the boot configuration correctly, sort out driver and VMD issues, and test through multiple full boot cycles before you pick it up.
Dave's Computers is a drop-off repair shop at 75 North Bridge St in Somerville, NJ (behind Bank of America), serving customers across Somerset, Middlesex, Hunterdon, and Mercer counties. Diagnostics are $75, credited toward your repair. Walk in Monday–Friday 10–5 or Saturday 9–2, or call (908) 428-9558 with questions about your specific setup — including whether your old drive is safe to keep powering on.
The most common reasons, in order: the original drive is still connected and conflicting with the clone, the boot files or boot configuration didn't transfer correctly, the BIOS storage mode changed during the swap, or Windows is missing the boot-critical driver for the new drive type (common when going from a SATA drive to NVMe). All four are fixable without reinstalling Windows.
No — at least not for the first boot. Clones share the original's disk signature, and Windows will force one of the two offline. Boot with only the new drive connected, confirm it works, then reconnect the old drive (and wipe or repurpose it).
Usually not. INACCESSIBLE_BOOT_DEVICE after cloning is a configuration problem, not a destroyed installation. Rebuilding the boot files with bcdboot, fixing BIOS settings, or one Safe Mode boot resolves the large majority of cases.
A healthy drive, no. A failing drive, absolutely — cloning is hours of sustained reading, which is exactly the workload that finishes off a weak mechanical drive. If your old drive shows any failure symptoms, don't re-clone it; have it professionally imaged instead.
Not for these fixes. Whether the clone came from Macrium, Acronis, Samsung Magician, Clonezilla, or a hardware duplicator dock, the failure causes — signatures, boot files, boot mode, drivers — are the same, and so are the repairs.