when i try to defragment any partition of my harddrive it just gives a message that windows defragmenter could not start ..and i am unable to defragment the hard drive. what is the cause of this ? when it try to defragment it using system mechanic 6 pro ..it takes hours and hours and theres not much progress ..also the cpu usage becomes 100 % and memory usage is also becomes very high ..so is this normal ..will i be able to defragment using system mechanic pro 6 atleast ?? or can the windows defragmenter problem be solved ?