screen savers

On a Microsoft Windows computer a .SCR file is a screen saver. As screen savers are just computer programs they are a useful way of inserting a virus into your computer. Typically SCR viruses come as an attachment to an e-mail. The text urges the recipient to click the attached file by promising perhaps a funny cartoon or enticing picture.
Once clicked the virus then installs itself onto your computer. As the SCR file pretends to be something else it is another example of a Trojan.
Perhaps the most famous example of a SCR virus is the SOBIG worm, which installed software to send spam. Another well-known example is the Friendship Screen Saver, also known as Yaha.E. However the well-publicised Budweiser Frogs screen saver virus turned out to be a hoax.