Aaron, in his self inflating importance, has again failed to give proper information on this subject....probably because he knows nothing about how things really work...
defragmentation will indeed speed up performance and overwrite some areas of your HDD...but not all...even if you defragment and then completely fill up your drive with data, there will still be possible areas where past data is accessible (even by free programs)...temp files, page files, etc....
about the only thing he has gotten right is that it is 'expensive' to truly retrieve data (and even getting that 'straight' answer was hard)....
for the truly worried I suggest totally wiping your HDD....
nuke your HDD
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So Long and Thanks for All the Files
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Beware of the big 3 insurance companies in Texas! Read your policies carefully (maybe you'll need a lawyer) Allstate, Farmers & State Farm are overextended and their 'coverage' is worthless...a true waste of your money
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