Microsoft Security Essentials (1.0.1963.0)

You are prompted to upgrade to the latest version of Microsoft Security Essentials (1.0.1963.0)

If you are running a previous version of Microsoft Security Essentials, such as version 1.0.1407.0, 1.0.1500.0, 1.0.1610.0, 1.0.1961.0, or an earlier version, you may notice an action item that prompts you to upgrade to the latest version of the program. You are prompted to do this through the Microsoft Security Essentials user interface, through a pop-up window, or through a "toast" message. Additionally, you may notice an "Important" or "High priority" download, Microsoft Security Essentials Client update package - KB2254596, on Microsoft Update that offers an upgrade to the latest version of Microsoft Security Essentials.

Important If you are running a beta version of Microsoft Security Essentials, we encourage you to upgrade to the latest version. By upgrading now, you help make sure that you have continuous protection against viruses, against spyware, and against other malicious software.

To determine which version of Microsoft Security Essentials that you are running, click About Microsoft Security Essentials on the Help menu. The Help menu is found on the upper-right corner of the Microsoft Security Essentials Home tab. You can find the Microsoft Security Essentials version number under System Information.

This issue occurs when you use an earlier or unsupported version of Microsoft Security Essentials.

http://support.microsoft.com/kb/2254596