click here for an article on defrag problems with links to Defrag ME and notes on how to install it. Apparently it's much better than it's predecessors. If that doesn't work try click here. for diskeeper lite.
Great freeware program. Doesn't get flummoxed if you keep working while it is doing its business unless disk activity is very intense, e.g. running virus checker at the same time. I'll post again when the defrag is finished. I have a 40 Gbyte drive about one quarter full.