To unzip a *.zip file you will need an "unzipper", a program which unzips a *.zip file, like WinZip. I highly suggest using WinZip because it's the archive program that most people use and is really easy to use. You can download the Evaulation Version for free if you don't have one already. Use WinZip to unzip the archive. Once the calculator files have been unzipped, you can send them to your calculator. If you don't know how to unzip an archive using WinZip or are having problems, you can ask me, but you really should consult the WinZip help or their Online FAQ.