After a lot of screwing around I found that 'middle button' solved the problem with my Logitech mouse.
BTW, I can recommend the Logitech VX Revolution for laptop use. Wireless, with a USB receiver that fits into the back of the mouse for travelling and a couple of extra thumb buttons that I find essential for AutoCad work.
[From memory, highlight the scroll button and then 'select function'.....a window with options appears with 'middle button' one of the options. all a bit counter intuitive, until you work it out]
Stu
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