Microsoft Windows 10, released a month ago, has already been installed on more than 75 million devices.
Previously, Windows marketing chief Yusuf Mehdi announced that the new OS was installed on more than 14 million devices within the first 24 hours of its release.
More than 90,000 personal-computer and tablet models have been upgraded to the new OS, which was a free update rolled out across 192 countries.
The Windows 10 app store also got a boost as it achieved six times more downloads per device than Windows 8.
Microsoft has promised its shareholders that the new OS will reach one billion users within three years.
CEO Satya Nadella expects Windows 10 revenues to be accretive in two quarters from now.
With the new OS, Microsoft has made several improvements including the introduction of a new start menu, voice assistant Cortana, Xbox app for gaming and a new Edge browser.