Now that Windows 10 improved many of the things that users complained, many people want to move to this new version of the system.
Windows 10 will be free for users officially licensed Windows 7 and Windows 8, for at least one year (although this period could be extended indefinitely into the future), and Microsoft has already published a method for those wishing to start testing the demo Windows 10 can do so with ease, using Windows Update, without dealing with ISO files.
Before upgrading, we must remember that Windows 10 is not yet ready, which will download is the preview version, so it can and probably will be several important bugs and errors.
Therefore it is only advisable to test Windows on a computer that does not have important files or even better, if they use Virtualbox and want to try it "virtually".
Upgrading to Windows 10 only can be done from Windows 7 or Windows 8. For this, you must first install an update that can be downloaded from the website
of previous version of Windows 10 by pressing the button that says "Start upgrade now".
By completing this installation, you must restart the system and when we go to Windows Update, we offer to install Windows 10 as a more updated:
How to download ISO preview of Windows 10
Those wishing to explore the contents of the installer of this new Windows 10 can also download the ISO image to the oldest, from this link