Can't activate windows after clean install

I just did a 'clean' install of Win 10 Pro 64bit on to my old Win 7 Pro 64bit HDD so that I could migrate my wife's Win 10 Pro 32bit apps and programs over the the 64bit OS.

First, I thought 'clean' meant also formatting the HDD because it didn't. I find all my old programs and folders still on the drive, including the Windows.old folder.

During the install, I used my wife's MS account to sign in as admin on the new system. Her account is valid at MS so I tried to activate the install but it wouldn't take. I even tried troubleshooting and selecting the 'I changed the hardware' but the message keeps coming up not a valid digital signature.

Do I actually have to do a clean install on the current 32bit OS HDD to get activation to work or am I doing something else wrong? One thing - I used the Media Creation Tool to download the .iso file on my PC not hers. Does that have anything to do with it? The only thing that's changed on her PC is the drive I did the 'clean' install on. The mobo has not changed so I can't figure out why no activation.

You could use the Windows 7 Pro key to activate Windows 10 Pro, if you still have it.

But no, you don't have to reinstall windows 10 on the 32 bit drive, if you install 64 bit on another drive on the same Motherboard, W10 should activate. Not certain if you can activate 2 instances of W10 at the same time on the same board without another key, Navy would know better.


The Clean command does not format the drive, it only cleans it, but you must not have done it correctly if all the data is still there.

You have to enter another command to format the drive.

Format fs=ntfs quick


Link Microsoft Account to Windows 10 Digital License Installation Upgrade Tutorials

Could you post a link to the "Clean" install instructions you followed? Or list the steps you took. It sounds like you may have done an upgrade.

What account you log in with has nothing to do with activation. Unless your trying transfer a license to new hardware. You can setup with a local account and Windows will activate. Was Windows 10 previously installed and activated on that PC?

The Product Code is good for 32 bit or 64 bit, its your choice which you use. The only thing locked in is the Edition, Home, Pro etc. You can't activate Home with a Pro key for example.

I was trying to upgrade my wife's Win 10 Pro 32bit to Win 10 Pro 64bit. In trying to upgrade, I installed an old Win 7 Pro 64bit from my PC (it is larger than her current drive). To be safe, I unplugged her current C:/ drive so it wouldn't get accidently over-written. So, same mobo, graphics card, different HDD.

Let me understand this - if the installation 'cleans' the drive, I shouldn't see any of the old folders then, correct?

The link I was using is: Clean Install Windows 10 Installation Upgrade Tutorials

Did you do a custom install and delete all the partitions on the drive? What gets left behind depends on what partitions were originally there, if you deleted them, and what partition you installed to.

You have to either delete the entire drive to unallocated space, or format the partition, it won`t format it unless you tell it to, just click on drive options.

Personally I would just delete it to unallocated space and let the installer make the partitions, and keep the 32 bit drive unplugged. You can boot into it after you hook it back up, simply press F8 when you turn on the PC to bring up the boot menu, then just choose the 32 bit drive from the list.

Clean Install Windows 10 Installation Upgrade Tutorial

It may not have worked had you tried it.

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