If it was installed previously, then the digital license should still be valid.
There are a couple of ways to go about it. All include using the Microsoft website to either install while online or to create a DVD disk or USB flash drive to upgrade. The website link is below and if you can't fix your ability to connect to the internet, you can use a different computer to create the installation media..
To create a DVD or USB flash drive which contains the Windows 10 install files, click on the link below, download the Windows Media Creation Tool and follow the prompts to let it create the media for you.
https://www.microsoft.com/en-us/software-download/windows10
ON the other hand, if your computer actually reverted back to Windows 8, it's entirely possible the internet adapter (either wireless or ethernet) needs to be updated so you can access the internet. You should be able to visit the computer manufacturer's website, or the network adapter manufacturer's website, then download and install the network adapter which is designed for your computer. Once that's done, if you can connect to the internet, it should be possible to visit the link above and follow the instructions to "Update Now" which will reinstall Win10 online.
It's your choice.
Hope this helps.
Grif
Hello All, Would really appreciate some help.
Windows 10 was installed free on my laptop last year. I never asked for it it just arrived. A few weeks ago I noticed that somehow my pc had reverted back to windows 8??????Anyway, it was working ok so I just left it. Now my laptop has crashed and I would like to do a reinstall of the free windows 10. I have been in safe mode this morning and saved all personal files and folders to a disk. I don't seem to be able to get onto the net even though I selected option of safe mode with internet.
I am not techy at all and have tried to find this answer through youtube etc but so much information out there I am confused.
I believe I can download windows 10 to my USB stick and do it that way?? How and where? Also, as the windows 10 I had orginally installed itself free I have no product code or anything like that.
Please can someone help me?

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