On July 29th, Microsoft rolled out Windows 10 to the world. In just four days, Windows 10 was installed on roughly 18 million devices (you can read our report here). Now, a new report suggests that Windows 10 has been installed on over 25 million devices, over one week after the release of the operating system. The unconfirmed report comes from Neowin, claiming Windows 10 installs have “surpassed 25 million and may be as high as 27 million.” If true, this is obviously a great figure for the software giant and shows that giving away an operating system for free is definitely worth while for the company. We’ll have more on this story once we confirm these numbers with our own sources.