You can still Get Winedows 10 Free and No Risk

[Geek-9pm]

Don't put off getting Windows 10 because of fear it will ruin you present Windows install. It is Free and Risk-Free.
No Product Key needed.
Put it on a 32 GB USB flash drive.  Yest it will boot from a USB drive.

For more info, just Google.
Install Windows 10 without product key
Boot Windows 10 from USB drive.

Or, just reply to this post with you question.

[Salmon Trout]

just reply to this post with you question.

Question 1: If you install Windows 10 without a product key don't you get you get an unlicensed version which may or may not continue to work in the future, which will display warnings, and isn't doing that against the terms of the license you agree to when installing?

Question 2: Isn't what you can boot from a flash drive the Windows install disk ISO? Don't you still have to install it on a PC?

[Geek-9pm]

Question 1: If you install Windows 10 without a product key don't you get you get an unlicensed version which may or may not continue to work ....

Question 2: Isn't what you can boot from a flash drive the Windows install disk ISO? ....

Answer 1:
Without the product key some features will not work. It will let you use the Internet and the Browse. Else where one pundit claims the blocked features are not very important to many users. How long you can continue is not known.
Here is a link the claims you can use it with no harm.
http://www.cnet.com/how-to/how-to-upgrade-to-windows-10-for-free-after-the-july-29-deadline/

Now let's travel into the future, maybe six months from now. You've decided you want to upgrade to Windows 10 after all, and you don't want to pay for the privilege. You're in luck. Since you already installed Windows 10 once on your PC, the software has been given what Microsoft calls a "digital entitlement." Yep, that's the same piece of text that's listed next to the Product Key entry.

Really? Read the whole story.

Answer 2:
Unlike earlier versions of Windows, the current version of Windows 10 can run from either an external drive or a USB drive it there is enough space available. To do it, at least 20 GB is needed. Here is a link from a reputable source:
http://www.partition-tool.com/resource/windows-10-partition-manager/install-windows-10-on-external-hard-drive.html
Apparently it can install to a USB flash drive and not depend on the hard drive to have any Windows 10 components. This is not new information. Check the link below[/i]
http://www.makeuseof.com/tag/create-portable-windows-go-usb-drive/
Written by Jessica Coccimiglio June 3, 2016

What if I told you that you could carry around your own version of Windows in your pocket, ready to run on any computer you may encounter, with all the programs you typically use already installed and set up exactly the way you like?
...

But she was reporting about Windows 8.1 so one might think you could do that in Windows 10. Really?
http://www.easyuefi.com/wintousb/faq/en_US/How-to-use-WinToUSB.html
That link claims Windows 10/8.1/8/7 can be made portable.

And there are many more link links on Google or Bing. 
.

[patio]

Just did a test of Win 10 on an external HHD as per instructions on your link

Guess what...it booted the 1st time...and never since.

Careful what you Post.

[Geek-9pm]

Just did a test of Win 10 on an external HHD as per instructions on your link

Guess what...it booted the 1st time...and never since.

Careful what you Post.

I just now installed it on an old desktop hasn't been used for months. It took two treys to get it up. .And then it gripe about my password. I forgot my password. After going around and around and around in the lost password loop it finally let me in. 

Explanation: My second monitor had gone out. So I had to swap with another PC that has my passwords.  So I could not get to my password list. So I asked Windows 10 to reset my password by email. My laptop PC did not have the password for my email account. Finally, I used my phone to retrieve the code from my email.

Amway, it is not the fault of Windows 10 that I forgot my password. Part of the problem was that I had to repair the old hard drive I was using.