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Remote Assistance: "Mit dem globalen Peer to Peer-Netzwerk konnte keine Verbindung hergestellt werden". Windows 7 Home Premium 64 Bit, all related Services active, connected by Wlan Dlink DIR 652, latest firmware, connected to Internet by gateway UPC Technicolor. Tested also directly over Technicolors Wlan Ethernet.
I solved this problem myself: A request to Upc gave a useless hint to forward a port for the application in the UPC Gateway, but I got in the meantime informations, that remlote control applications in general are unwanted by UPC network for security reasons, so there is no hope for support from this side, Furthermore the feature in question involves IPv6 not yet implemented by UPC. Thanks so far