Solved Upgrading 8.0 to 8.1 With ISO

The method for obtaining a retail Windows 8.1 ISO has been published and re-published. It seems that most people who are interested in the ISO want to use it for a clean install. I respect that, however I want to upgrade my copy of (retail) Windows 8.0 Pro to Windows 8.1 Pro.

Can I use the retail Windows 8.1 ISO to upgrade from 8.0 Pro to 8.1 Pro?

Yes, because Microsoft doesn't have real upgrade versions anymore. Windows 8.1 only comes as a full version but it can be used to do an upgrade as well.

I found this info in the Microsoft Store:

Windows 8.1 Pro offers enhanced features to help you easily connect to company networks, access one PC from another, encrypt your data, and more.

Important: Windows 8.1 Pro full version is for Windows 7 users only. Currently running Windows Vista or XP? First upgrade to Windows 8 Pro. Upon installation you can update to 8.1 for free.

Already running Windows 8 Pro? No need to buy Windows 8.1 Pro—you can update to Windows 8.1 Pro for free through the Windows Store.


I find this information a little strange, because I installed Windows 8.1 Pro on my laptop after I had deleted all my partitions on it. So, you can also install it on a completely clean system.

Thanks for your help.

I also saw that information on the Microsoft website. It was confusing at first, but now I understand: In typical fashion, Microsoft only describes what it wants you to do, not what you can do.

Microsoft wants you to upgrade from 8.0 to 8.1 from the Windows Store, so it doesn't mention that you can upgrade from the ISO.

That's right.

They also mention you can't use Windows 8.x on a XP or Vista PC, but the laptop I'm using right now had Vista pre-installed back in the day. And my Windows 8.1 is now working very nicely on it. I do get an error of my video driver sometimes, but that's because I still use the Vista drivers for it. But that's not a big deal. It just crashes -> recovers and you can work on for another few hours without losing any work.

And... it's still working much smoother than when I had Vista installed on it. So...

Option Two.
http://www.eightforums.com/installa...retail-windows-8-1-windows-8-product-key.html

The linked solution reads:

"A Windows 8 product Key can not be use[d] to Upgrade to Windows 8.1."

I believe that means that a Win8 product key can't be used to clean install Win8.1. (Although there are work-arounds for that.) It doesn't make sense that you can't upgrade to Windows 8.1 from Windows 8 unless you have a Win8.1 key ... the upgrade is free for Win8.0 users.

Daddyman said:

The linked solution reads:

"A Windows 8 product Key can not be use[d] to Upgrade to Windows 8.1."

I believe that means that a Win8 product key can't be used to clean install Win8.1. (Although there are work-arounds for that.) It doesn't make sense that you can't upgrade to Windows 8.1 from Windows 8 unless you have a Win8.1 key ... the upgrade is free for Win8.0 users.

Click to expand...

I did it like this:

I booted with a Windows 8.1 Pro ISO that I had written to an USB stick.

While going through the setup, I deleted my partitions and then let the setup of Windows 8.1 automatically make a new partition to install itself to it. However, you can also do an upgrade here from Windows 8. But because Windows 8.1 is not really an upgrade but a new OS, I prefer to do clean installs.


There is only one other thing you need to do before you boot from the USB stick.

Use notepad and add following text in a new document:

[EditionID]
Professional
[Channel]
Retail
[VL]
0

and safe this as 'ei.cfg' to the 'sources' folder on the USB stick.

This will make sure that the setup doesn't ask for a product key until Windows 8.1 is installed. Only then it well ask for your key and you can use your Windows 8 Pro key here.

If you don't do this, you will need to have a Windows 8.1 Pro key at the beginning of the installation.

Daddyman said:

The linked solution reads:

"A Windows 8 product Key can not be use[d] to Upgrade to Windows 8.1."

I believe that means that a Win8 product key can't be used to clean install Win8.1. (Although there are work-arounds for that.) It doesn't make sense that you can't upgrade to Windows 8.1 from Windows 8 unless you have a Win8.1 key ... the upgrade is free for Win8.0 users.

Click to expand...

Just use the key at the end of the post.

I believe that the reason you were able to do a clean install of Windows 8.1 after formatting your hard disk is because the 8.1 installer read your existing Windows key and recognized it as a qualifying version of Windows before you formatted your disk. Thus, the installer knew you were qualified to install Win8.1. This a supported method for doing a clean install. It's the same way I was able to format my Windows 7 partition to do a clean install of Windows 8.

Had erased your hard disk before you first installed the upgrade media, I don't believe the install would have proceeded.

Daddyman said:

I believe that the reason you were able to do a clean install of Windows 8.1 after formatting your hard disk is because the 8.1 installer read your existing Windows key and recognized it as a qualifying version of Windows before you formatted your disk. Thus, the installer knew you were qualified to install Win8.1. This a supported method for doing a clean install. It's the same way I was able to format my Windows 7 partition to do a clean install of Windows 8.

Had erased your hard disk before you first installed the upgrade media, I don't believe the install would have proceeded.

Click to expand...

Hmmm, could be. Well, I'm planning to do a fresh install of my main PC tomorrow. I'll first delete my partitions and then boot from the USB stick. I'll let you know if I could install Windows 8.1 or not.

I have done it already. I had forgotten the F1 was on TV today, so I had some time to reinstall my PC while watching the F1.


I can tell you, the installation I explained works on a complete empty hard disk. I had removed my partitions from the hard disk and then when I tried to boot my PC, it gave an error message. The PC couldn't find anything to start with, of course.

I then booted from my USB stick with the Windows 8.1 Pro 64bit ISO installed on it and it started the installation.

With the ei.cfg installed in the source folder, I didn't need to input a Windows 8.1 key.

After the installation was done, it asked me for my key and I entered the Windows 8 Pro key from the upgrade disc I have bought and then it went on with preparing my system for its first start.

After it had started, I noticed my Windows 8.1 Pro wasn't activated, but I just needed to call a local free number and go through the standard procedure to confirm that this key wasn't being used on another PC.

And my freshly clean Windows installation is now ready on my PC. (The other software I use I'm going to install tomorrow.)


There is also something else I want to add. Now that I did this install, I paid a little more attention to the process.

At a certain point, you can choose for an upgrade or custom installation. I needed to choose the custom, of course. But for fun, I also tried the upgrade. I then got a message that I needed to start the PC with my installed OS, and from there, run the setup of Windows 8.1 Pro.

So, for an upgrade, you don't need to boot from the USB stick, but you need to boot your current OS and start the setup from there.

Because I had never done an upgrade, I didn't knew this, but I just wanted to give you this information.


I hope this will help you prepare your system!

Best regards,
Rudy

That was very helpful information! Thank you very much.