If I've got an hardware HDD duplicator and two identical harddrives (by "identical" I mean same brand, exact same model, but not the same serial number) and if I use the duplicator to make an exact copy of the drive which a removed from a Windows 8.1 machine to an empty drive, can I then place the copied HDD (the one previously empty) in the Windows machine and boot from there as if nothing happened?

Would this work without requiring weird Windows activation / registration features due to the HDD's serial number not being identical?

And it works, does it work an unlimited number of times? Or does it work, but only as long as I don't change my drive x times?

  • Edited my question to make it clear I was talking about hardware HDD duplicators. – Cedric Martin Feb 18 '16 at 1:06
  • 1
    Yes; that's the point of a HDD duplicator – Ramhound Feb 18 '16 at 1:37

Very likely that would be the case - it would be no different from doing a duplication via dd in linux.

In addition, you'd be running on (mostly) the same hardware - a hard disk replacement dosen't seem to be enough to trip off activation, and drivers would entirely be the same.

It would quite certainly work

| improve this answer | |
  • 1
    yup but under Linux (which I run too), there's no re-activation required by Microsoft if, say, I change the motherboard and the GPU and the CPU. With Windows I'm pretty sure that at one point your Windows license was "tied" to the computer as when you bought it and that you were allowed to change at most x components before having to ask for a new serial number, explaining why you did change the components. My concern is mostly about some Microsoft anti-copy / re-registration protection that could kick in. – Cedric Martin Feb 18 '16 at 0:41
  • 2
    I've swapped hard drives up to 3-4 times on a system. Considering your storage is the most likely thing to fail, its the least likely thing to trigger off a reregistration. – Journeyman Geek Feb 18 '16 at 0:45

Question Clarification:

I am not certain if you are asking if you can Boot from a duplicated Windows 8.1 hard drive, or if there will be activation issues -- or both ...

But, the answers are very similar.

Quick Answer

In your scenario, you are more likely to have boot issues, rather than activation issues, (both highly unlikely).

Just be sure:

  1. Do NOT change the BIOS mode, (UEFI or Legacy).
  2. Do NOT change the Partition Format, (GPT or MBR).
  3. DO make sure you copy the small EFI and MSR partitions, (will be there if you are using BIOS UEFI mode.
  4. DO Verify your BIOS Boot Disk Priority settings. Somewhere, it specifies the boot order, (USB, or Hard Drive first). This should automatically update, but if there is an issue check this too.

Change these afterwards, if you need -- but research first; it's complicated.

Risks Regarding Activation

On newer computers, Windows 8 stores the Product Key authorization in the UEFI BIOS. (UEFI Activation Thread, on Microsoft.com, link).

It will auto-magically activate/validate with this product key -- no problem ... unless ...

You may have installed it from a disk and entered the provided product key.

You may have to enter it again, but it shouldn't be necessary.

If there are issues, Windows 8.1 will still "boot" -- but prompt you to resolve activation issues if it detects problems, (you won't be able to do anything else).

Risks Regarding Booting

The biggest concern is /perhaps/ a booting issue, (in your BIOS config, or the MBR on the hard drive).

Boot Order:

Of all of the potential issues, this is the most likely -- though unlikely:

You should go into your BIOS, and make sure your new Hard Drive is set with the proper boot priority -- it will have a different serial number, and may not have updated, (highly unlikely).

If Windows has any issues related to the Hard Drive Serial Number, it should be easily fixed by Windows during the Startup Repair -- if the BIOS was updated correctly.

UEFI vs. Legacy BIOS:

On hard drives, there is now a standard UEFI partition if the BIOS is set to UEFI.

If your BIOS was set to UEFI mode, make sure you copy the UEFI/EFS partition from the other drive as well, (and the MSR partition too if it is there).

Also, if your BIOS was set to UEFI, don't change it to Legacy, or vice versa.

Windows startup repair has incredible difficulty with this kind of change.

GPT vs. MBR:

Although you said this was a low level bit for bit disk copy -- there are other tools that don't do it this way, and are more efficient.

For example: some just make disk image files, and allow you to restore the data onto a partition with a different size. These disk copy methods are significantly faster.

BUT -- If the tool allows you to resize partitions, it may also allow you to set the disk partition type to either GPT or MBR.

YOU MUST use whatever you used on the first one.

Windows Startup Repair has incredible difficulty with this kind of change -- and will likely fail, (Even Windows 10).

| improve this answer | |
  • 1
    thanks a lot... (btw when I wrote "HDD Duplicator" I was talking about an hardware HDD duplicator in case that wasn't implied by my question). I think these hardware duplicators do bit-per-bit identical copy of the HDDs right, including the MBR? And including the UEFI partition? Also what should I update in the BIOS config seen that I'd be replacing my HDD by another identical one? – Cedric Martin Feb 18 '16 at 1:06
  • 1
    Cedric (A.) I hope I clarified the BIOS setting point a little bit more in the post, but this is likely unnecessary. (B.) Some disk copy tools skip empty data for efficiency, (like Windows drive image); (C.) Even low level disk copy tools allow you to pick and choose from the disks/partitions being copied -- so, grab all the partitions from that disk just to be sure, (especially the EFI and MSR partitions if they exist). (D.) Some tools allow you to resize partitions, and even change the partition type. This is incredibly risky, and best avoided if possible. – elika kohen Feb 18 '16 at 1:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.