How to upgrade 1511 from Home to Pro?

Starting with Version 1803 one must have a Digital License for Pro in order to change to Pro while Windows is online.  The installer at boot will also choose Home if there is an embedded Product Key for Home, as previously.  So there is a new procedure to change to Pro from Home:

1. Go offline by choosing Airplane Mode in Action Center.
2. Enter the Generic key to install Windows 10 RTM to change to Pro Version.  This does not require being online to complete the change to Pro version.  
3. Go back online to insert the Pro Product Key which requires being online to activate with MS servers.

I'm not having any luck figuring out how to upgrade from Home to Pro with an existing key.  My system has been running Home and is currently running version 1511.  I've decided to go ahead and use an existing key to upgrade to Pro.  I did a clean install, expecting to be asked to specify a version and provide a key during install, but was never asked for either.  The installer simply formatted the hard drive and installed Home and activated it, with no input from me after the install started other than agree to the terms and tell it my language.

OK, no problem I thought, I'll just go to the Activation setting and give it the new key from there.  However, if I tell it I want to change the key it comes back and says the key I'm giving it can only activate Pro and I'm running Home.  If I go the Store route and tell it I already have a Pro key, it gives me the same message - it tells me my key is for Pro but I'm running Home.  Nowhere along the way does it offer to take my key and give me the upgrade, rather it implies that I must somehow magically upgrade it myself before changing the key.  And that would be fine if I could figure out how to do that.

Anyone know how to force an install of Pro when the installer automatically installs Home with no option given to change it?

Why install such an old version when the latest media is avaialable at all times to create bootable media using the Media Creation Tool?  http://windows.microsoft.com/en-us/windows-10/media-creation-tool-install

Then if you boot the media correctly you should get a boot menu to choose Pro version if that's the Digital License you already have on the PC.  If it's a Windows 8 PC with embedded Home Product Key it still might force Home version, though. 

The solution then is to go offline (using Airplane Mode in Action Center)  to change to Pro version by inserting the Generic Pro Product Key:  http://winaero.com/blog/generic-key-to-install-windows-10-rtm/

Once it changes to Pro, go back online to insert the valid Pro Product Key to activate Pro or wait for it to phone  home to activate with an existing Pro Digital License. 

I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.

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