.... I'd like to add that you do have a few other options, if the USB method gives you fits ... or if you simply would rather not have to buy a different USB device = create a Windows 10 installation DVD using Microsoft's Media Creation Tool. The tool downloads the latest stable public-release version of Windows 10, and allows you to create a bootable DVD. (and, of course, if you still have a previous version of Windows installed on the target computer, you can do a complete installation (whether in-place, or "clean") online (you simply choose whether or not to keep things from your previous version of Windows).
To upgrade online, simply visit the Microsoft "Get Windows Now" site, and select "Upgrade Now"....
https://www.microsoft.com/en-au/software-download/windows10
If instead you wish to create a
Windows 10 installation DVD:
1) Visit that same site, but
scroll down to the section "
Need to create a USB, DVD, or ISO?"
2) Click on the blue option button "
Download tool now"
Once the download is complete, double-click
MediaCreationTool.exe
3) "Getting things ready" will appear for a bit.
4) Agree to the License Terms by clicking on
Accept
5) Again, "Getting a few things ready" will appear.
6) On the following screen, select "
Create installation media for another PC".
7) And click
Next.
8) Select your preferences:
language, Windows 10 version, bit-depth (the defaults are English, Windows 10, 64-bit)
9) Select
ISO file.
If the iso is created on a computer already running Windows 10, simply put a blank DVD in the optical drive, right-click the .iso file you created & select "burn disk image". Otherwise use a DVD burning capable program (Roxio, Nero, Sonic, CyberLink, etc.) to create the bootable DVD -- look for a "burn image" option. You must use that special command, because simply copying the file to a DVD doesn't make the DVD bootable, it must be written as a system image (otherwise it ends up as a normal storage DVD that happens to have an .iso file on it).
.... this is all just in case you want to try something else... The USB method is also a good method, once you have everything ready for it.
[P.S. ... and, of course, make sure that the target partition you wish to install Windows 10 on has at least 20 to 25 GB of space for comfortable use.]