In the former case, built-in games and premium features like Windows Aero are disabled, and the system is rebooted every hour in the latter case, certain premium features are disabled and some content is not available from Windows Update. The reduced functionality varies based on whether the operating system is simply out of grace or has undergone a failed activation.

In Windows Vista RTM, after a grace period of 30 days, the operating system will boot only into a reduced functionality mode.

In Windows XP, Windows Server 2003, and Windows Server 2003 R2, after a grace period of 30 days, the operating system cannot be used at all until the activation process is completed successfully.

If activation is not performed within the grace period or fails because of an illegal or invalid product key, the following restrictions will be imposed on the user: On each boot, Windows confirms the presence of specific information stored in the BIOS by the manufacturer, ensuring the activation only remains valid on that computer, even if the product key is used on another machine. In this case, the copy of Windows installed does not use the product key listed on the certificate of authenticity, but rather a master product key issued to OEMs called a System Locked Pre-installation (SLP) key. If Windows is pre-installed on a computer by an original equipment manufacturer (OEM), the operating system is automatically activated without the need for interaction from the user. Businesses using this licensing system have the option of using Microsoft's activation servers or creating and managing their own. Programs purchased under this license must still be activated, with the exception of Windows XP and all versions of Office released prior to Office 2010. Ĭertain versions of Windows and Office are available under a volume license, where a single product key is used for multiple installations.

Throughout this grace period, the user will be periodically reminded to activate the program, with warnings becoming more frequent over time. Immediate activation is not required following installation, but the program must be activated within a specific period of time in order to continue to function properly. When installing a retail copy of Windows or Office, the user is asked to input a unique product key supplied on a certificate of authenticity included with the program, which is later verified during activation.

Microsoft key has expired