Best way to clone MBR disk to GPT, under Windows 10

August 11, 2021 9:46 AM

My question is essentially a follow-up to my earlier ask. I'm looking for advice on how to clone a Windows boot drive from MBR to GPT.

I have a Windows 10 PC. The boot drive is a 1TB M.2 drive (NVMe). It's partitioned in MBR. I want to play it safe, so I don't want to do an in-place conversion to GPT.

I recently bought a second 1TB M.2 drive, along with an enclosure with a USB-C connector. My tentative plan is to clone the boot drive to the new drive, making sure that the target drive is partitioned in GPT. Then I'll shut off the computer and swap-out the original boot drive with the new one. This way, if something goes wrong with the cloning process, I have the original drive to fall back on.

I've never done this before. When I Google it, I get a bunch of hits for utilities that promise to do this for me, but they're all made by companies I never heard of.

I am not averse to paying some money for software, as long as it's reliable and will get the job done easily. On the other hand, if there is some free solution that works just as well, then of course I'd prefer not to spend more money.

(Incidentally, all my data is backed up to the cloud already.)

posted by JD Sockinger to Computers & Internet (6 answers total)

The last time I did this, I used Macrium Reflect. In my case, this was moving stuff between two NVMe drives, stuff off of a Windows Storage Spaces drive and onto a standalone disk, and then moving stuff again onto another NVMe drive - all worked with no problem though it's worth noting that in some cases I had to go into Disk Management to re-size the partitions. (This was because some of the new drives were bigger, and Macrium's clone process doesn't expand the cloned partition to take over the entire drive. This may not be a problem in your case.) You'll have to check to make sure the newly cloned boot drive is indeed in GPT format as generally clones are just that so they'll be largely similar to the source - but at that point converting it is a lot less risky (to the extent that it's risky) since you'll have the backup. The free version is what I used here; next time I'll probably buy a license since it works quite well.

I also tried AOIME Backupper. I've used this in the past successfully but it's a bit annoying with upsells and they've since changed things and the clones I wanted to do weren't covered by the free version anymore. I heard about that one from this JayzTwoCents video on cloning your drives. (It did work well before - it was just annoying me and I then didn't want to pay for it to do the simple clones I wanted to do.)

Furthermore, I also tried the pack-in copy of Acronis that came with the Sabrent SSD enclosure I got. That was just straight up useless - if it doesn't see any Sabrent stuff on your machine it doesn't work at all (unsurprisingly, but I needed to move stuff around before using the enclosure or the also Sabrent SSD I was swapping in) and when you did pass the OEM checks it was incredibly slow - it took literally all night to clone the one drive I bothered with before switching back to Macrium, and Macrium got the other drives cloned within a few hours. (These were all 1TB+ drives, each with at least 500GB of used storage, so it's not like there was just less data. ) Maybe it's better if you just buy it but I wasn't about to do that.
posted by mrg at 10:23 AM on August 11, 2021

(As a quick aside, I've also done the MBR-to-GPT transition a couple of times, usually on systems with Docker and WSL environments and stuff, and they've generally all gone well. Or, at least, I don't recall one going bad. Have had a couple instances where it refused to do it, but those have been cases where the hardware didn't support it. That is a pretty big change to make so caution is very warranted here but I did want to note that did go well, at least in my experiences.)
posted by mrg at 10:40 AM on August 11, 2021

You could use a dumb tool (all the way to something as basic as dd from a Linux LiveUSB) to do the clone and then run the in place conversion on the clone.
posted by wierdo at 2:07 PM on August 11, 2021

I recently had to do this transition - my fresh Windows 10 installation set me up with MBR (still can't figure out why that happened) and I didn't discover it until I tried to duplicate the disk years later.

Fortunately, Microsoft has a built-in utility to do just that: MBR2GPT

Would it work to just clone the drive over as-is, then run MBR2GPT for the conversion? It worked well for me and I'm still using the machine to this day.
posted by owls at 2:18 PM on August 11, 2021

>I recently had to do this transition - my fresh Windows 10 installation set me up with MBR (still can't figure out why that happened)

I guess that your system presented the drive to Windows as SATA not AHCI in some state of Compatibility Support Mode, falling back to Old Ways for safety's sake.

To answer the question: Linux LiveUSB, most likely GPartEd, for cfdisk and/or fdisk to set the layout of the clone. You will find that GPT reserves more space for its layout data, which might make your clone not-absolutely-identical.

Plus: create another, extra, backup of the data you may lose.
posted by k3ninho at 4:15 PM on August 11, 2021

Best answer: Update: I ended up solving the problem by buying the Pro version of MiniTool Partition Wizard. This product easily and quickly converted my boot drive and two data drives from MBR to GPT. Before settling on this paid utility, I tried using Samsung's free utility Samsung Data Migration (didn't work for the intended purpose, although I did use it to make a clone as an emergency backup). I also tried to do an in-place conversion using Microsoft's built-in Windows app, MBR2GPT. This didn't work, either. It gave me some kind of vague error message that I couldn't figure out.

For the people who recommended Linux tools: Thanks, but my knowledge of Linux is severely limited. I wouldn't know where to start.
posted by JD Sockinger at 9:35 AM on August 15, 2021