Some of our larger files have been 'zipped' (compressed) to make them easier to download.
Many computers will already have software to unzip these files. But if yours does not, IZArc is a free piece of software which will allow you to do so.
Click on the image below to go to the IZArc site and download IZArc.
(Note that their site has a number of adverts for other pieces of software, so take care that you download IZArc and not something else!)