Q: A friend sent me an e-mail with an attachment with a .RAR extension. How do I open that?A: First, make sure your friend really sent the attachment. Some e-mails are generated by evildoers who "spoof" or imitate innocent people's e-mail addresses and send infected attachments. Once you've verified it's legitimate, then you need to open the attachment. There are several free programs that can open compressed files such as RARs. The one I use is IZArc. IZArc will extract RAR, ZIP and many other archives. The program can be found here: www.izarc.org.