Windows 10 inaccessible boot device after clone

A few weeks back I received a 1TB Western Digital Babsence SN750 M.2 SSD, boasting an outstanding 3470 MB/s check out speed on the packaging. I already had a SATA SSD installed in my gaming/photo editing PC. However, those specs got me to pick up a screwdriver and install the new M.2 SSD. The physical installation is dead simple: rerelocate graphics card, install M.2 SSD, reinstall graphics card. I wasn’t really looking forward to a full reinstallation of Windows 10 though. There’s simply also many applications, settings and licenses on that mechanism that I didn’t desire to reproduce or re-enter. Instead, I wanted to clone Windows 10 from SATA SSD to M.2 SSD.

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After a little bit of research, I finished up through Macrium Reflect, which is freeware disk cloning software program. Long story short: I cloned the old SSD to the M.2 SSD, rebooted from the M.2 SSD, and… was greeted through a selection of errors. The major recurring error was Inobtainable Boot Device, but in my troubleshooting attempts I witnessed many type of more errors.


While googling for options, many solutions stated the bootrec.exe, bcdmodify.exe and diskpart regulates to settle the boot worries. In the end but, my difficulty had actually more to do with the difference in between BIOS and UEFI, and exactly how storage tools are addressed. I’m still not 100% sure why, so feel free to comment below!

I was running a really old BIOS, and never properly collection it up once I initially set up Windows 10 many type of years ago. In that old BIOS, my storage tools were collection to Legacy mode rather of UEFI. This is probably bereason it ran Windows 7 or 8 a few years ago; or simply bereason I never changed it from the default mode. What this in result means is that my old SATA SSD was formatted with MBR rather of GPT (it’s a partitioning scheme). It likewise indicates that my Windows 10 installation had actually a “device partition” instead of an “EFI mechanism partition”. Tbelow is a important difference right here.

All this supposed I could clone and play about through bootrec and also bcdmodify all day lengthy, but it wasn’t going to solve my problem. I maintained acquiring Inavailable Boot Device errors, the bootrec and bcdedit commands didn’t discover my Windows installation, and also transforming drive letters through diskpart didn’t perform anything either. So what did permit me to clone clone Windows 10 from SATA SSD to M.2 SSD? I had to upgrade to a UEFI Windows 10 installation, with a GPT partition style! Fortunately, that’s not as hard as it sounds.

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Preparations: backup and unplug other drives

First of all, the mandatory disclaimer. Commands in this post have the potential to ruin your installation. If there’s anypoint necessary on your drives, make a backup. I’m not to blame if you lose information.

Next off up, unplug other drives. I have actually a 6TB WD Red drive in tbelow too, so I unplugged that to make certain I wasn’t going to accidentally format it. Leave the PC cover off, because you might be unplugging and also connecting drives a couple of times.

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It also helps if you have actually an additional system/lapheight and a couple of 4-8GB USB sticks nearby, so you deserve to develop a couple of tools that will certainly assist along the means. I created a Windows 10 Recovery Drive and also (on advice of a dear friend), developed a CloneZilla USB stick.

A quick examine to view if this short article uses to your instance is to open up disk manager (right-click the Windows “start” button, choose disk management). Locate your old SATA SSD drive, best click the drive and also choose properties. Navigate to the volumes tab. In the Partition style field, you should view Master Boot Record (MBR). If you currently check out GUID Partition Table (GPT), this settle could not use to you. Do proceed reading if your curious though…