It’s no secret that Windows 8 hasn’t exactly been Microsoft’s most successful operating system, but the company is looking to turn things around next year with the release of Windows 10. According to the latest update on the Windows blog, over 1.5 million users are now registered for Windows Insider. Even more impressive: 450,000 of them are “highly active” on Windows 10.

READ MORE: New Windows 10 build leaks, revealing new consumer features

More users are active on the Windows 10 preview than any other preview or beta program the company has ever run. Microsoft’s team is especially excited to see so many users latching on to the preview because it is giving them a chance to fix things they might not have discovered otherwise.

“The reports you send us, both from automated things like crash logs and manually via the Windows Feedback app, are helping us shape the product,” wrote Microsoft’s Gabe Aul.

“My favorite recent example of the latter is a bug that would have been really tricky to catch with test automation or by other means: In certain circumstances (very rare) the OneDrive icon in File Explorer can be replaced by the Outlook icon! That’s the kind of fit and finish bug that real usage at scale by Windows Insiders helps us find and fix.”

Microsoft has already fixed over 1,300 bugs reported by Insiders and has occasionally adjusted the user experience to suit the audience as well.

Expect to see the next build of Windows 10 in early 2015.