Microsoft revealed last year that it was planning to be more aggressive with its Windows 10 upgrade plans for existing PCs. Starting this week, Microsoft is recategorizing Windows 10 as a "recommended update" in its Windows Update system. That means the Windows 10 upgrade process will download and start automatically on thousands of machines.

Windows 10 will automatically download if you're on Windows 7 or Windows 8.1

While the upgrade process starts automatically, existing Windows 7 and Windows 8.1 users will have to choose whether they upgrade to Windows 10 or not. Windows 10 will automatically download and start the upgrade process, depending on your Windows Update settings, but you can opt out and not receive nagging prompts to update. Windows 7 and Windows 8.1 users on a metered connection will have to turn off automatic updates to prevent the Windows 10 installer from downloading automatically.

Microsoft confirmed the change in a statement to The Verge. "As we shared in late October on the Windows Blog, we are committed to making it easy for our Windows 7 and Windows 8.1 customers to upgrade to Windows 10," says a Microsoft spokesperson. "We updated the upgrade experience today to help our customers, who previously reserved their upgrade, schedule a time for their upgrade to take place."