I gave up on the modem. An expert friend has installed a router instead. This connected OK with windows.
However, there is still a problem with Linux. Despite the modem being discarded. it still trys to connect through the USB. My friend cannot find the particular script which is doing this. However connection can be made by going into Yast2 and telling Linux to ignore the USB. When this is done connection works OK. He is going to teach me how to do it Thanks. Fallschirm