This article provides instructions for downloading and installing Microsoft Security Essentials on a Windows 7 device.
Download and install
Visit http://www.microsoft.com/security_essentials/ and choose the Download it free* today button. The website should recognise your operating system version and instigate a download, if this does not happen, choose the link that corresponds to your operating system version.
When the file download box appears, choose Run or Save(if you wish to install later).
If User Account Control is turned on, you will receive an alert asking whether you would like to make changes to your computer.
Choose Yes. If User Access Control is turned off, skip this step.
If you are then prompted with a security warning click Run.
The Microsoft Security Essentials installer will then begin. Follow the installer, ensuring any other anti-virus programs have been uninstalled first and keeping all default settings.
Once the installation has finished, you should receive a message to say the software has installed successfully. Click Finish.
Microsoft Security Essentials should then automatically update and perform an initial scan of your system.