Thanks, was referring to the shut down button from the LXDE logout session which I'd assumed was the standard way of fully closing down. However, have now used the LX Terminal comand as you suggested and pleased to say it does reliably close everything down. Thanks everybody for the help
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I'm a beginner and can't seem to get the shut down button to work. When I select "shut down" nothing happens. Anybody know if I am doing something wrong ? Is there a command on LXTerminal to shut the R-Pi down ?