I finally managed to download MapWindow GIS.
It was a nameserver. My provider coluld not resolve the gisci.isu.edu (sub)domainname. So if found out the IP-Address ( 134.50.100.100) and substituted it for the name.
The download link that worked is http://www.mapwindow.org/download.php?fi...ails=1&dl=2

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