You'll be asked to designate a file name and a location. Whether you use the desktop or some specific directory, make certain to save all your Web material in the same place. This will prove particularly important when you upload the material to the network. Choose anything you want, but do not insert any spaces. In addition, it's better not to use capital letters.
Web addresses are case sensitive, and people often make mistakes with capital and lowercase letters.
Better to avoid the problem altogether by using lowercase. This is not the file name. Instead, it is the text that appears in the blue bar at the top of the Netscape window. The composer will save your file. You can now exit from the Netscape Composer window.