How to upgrade from 32bit to 64bit with WindowsUpgradeOffer?

Question

Microsoft

I asked here a question to technical support about the possibility of upgrading Windows 7 Home Basic x86 to x64 using the WindowsUpgradeOffer program.
Here are excerpts from their Q&A
Is it possible for Windows 8 to upgrade from a previous 32-bit version of Windows to 64-bit?
You cannot upgrade from a 32-bit to a 64-bit OS using the Windows Update Assistant.
And in the meantime:
Can I use the Windows 8 Upgrade SKU to upgrade to Windows 8 from my existing Windows OS?
Yes. Windows 8 Upgrade SKUs are for use on a computer licensed for an earlier version of Windows (Windows XP SP3 or later). Depending on the version of Windows you are upgrading from, you may need to clean install Windows 8.

I was wondering if the upgrade assistant can't do that, can I do a clean install? The following response was received:
Good afternoon, Maxim.
Thank you for contacting the Microsoft Information and Support Center.
This promotion provides for downloading and installing exactly as an update, since authentication is required, but then you can hand over a clean reinstallation from media, which can be ordered additionally.

Technical support answers, as always, are not complete and detailed.
Can someone explain to me, fool, how this will all look like? If he plans to authenticate, then I stick in the update disk, he tells me that everything is OK, and activates the key via the Internet or what? Then, as I understand it, I can make a clean installation with this key? I also somehow don’t want to order the carrier for another 15 bucks. I still plan to buy another version in electronic form (the one for $69 on sale). As I understand it, I can use it. Or how is this to be understood?

Answer 1

I think that you will have to upgrade to 32-bit eight, and then install 64-bit from scratch with the same key.
The boxed version of Win7Pro installs and activates with one key both x86 and x86-64.