Hi, I'm assuming that you've done a 'thorough' scan when you've run
scandisk?
After I had done that, I would try leaving the machine alone to defrag for
quite some time. (overnight or longer?)
I'm suggesting this because I have a friend who insisted that her 
defrag was
freezing also, but when she left it overnight, it defragged on it's own
eventually.
These seem to be the most obvious problems to start with
Hope this helps, 
Michele sayer

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