Announcing Windows 10 Insider Preview Build 10525

With the general availability of Windows 10, the Windows Insider Program will focus on building and delivering Windows as a service by updating Windows 10 with new features and functionality on an ongoing basis. As always, Windows Insiders will be the first to see these new features and changes.

If you’re already a Windows Insider and have been running Windows 10 Insider Preview builds – there is nothing you need to do. You will automatically be upgraded or you can upgrade your build via Windows Update. If you want to get a Windows 10 Insider Preview build installed on a PC running Windows 7 or Windows 8.1, you should first upgrade to Windows 10 using the free upgrade offer* available to qualified, genuine Windows 7 and 8.1 devices. From there, you can opt in to the Windows Insider Program via Settings app > Update & Security > Advanced options under “Get Insider builds”.

Windows 10 Insider Preview is intended to be installed on genuine Windows 10 devices – before upgrading to Windows 10 Insider Preview Builds or reinstalling Windows 10 please ensure your device is activated. To confirm go to Settings > Update & security > Activation. With the launch of Windows 10 we introduced device based activation. If you’ve previously activated a genuine copy of Windows 10 on your device, you’ll be able to activate Windows 10 Insider Preview builds of the same edition without the need to enter a product key. This will also enable you to re-install the latest public release of Windows 10 without entering a product key if you no longer want Windows Insider Preview on your device.

More details at Windows Blog