Dear Henk, thank you for the hint djvu, but I doesn't work. I alway arrive at Winzip where they want me to register for a test version. I am not interested. But it is important for you to know that I am absolutely stupid regarding PC and internet and electronics etc. I am a mechanical type from the steam era. Too old. So it is certainly my fault that I cannot deal with djvu. Who cares, it's not important. All the best to you!
Fred, what happens it that you have Winzip installed and it expired and it tries to open it when you click the link. You have to uninstall from your system it so it removes association of Zip files with WinZip, then try downloading again. To uninstall, most likely you need to go to your Control Panel and go to Programs and Features if you're on Windows Vista or Windows 7. Then find WinZip and click Uninstall on top.