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I ran defraggler last night because and I let it run while I slept. I woke up this morning and it still told me my hard drive was 20% fragmented. So I ran it again before I left the house for a couple hours. I come back, and it still says 19% fragmented.

What is the reason for this? Is it normal or is there a problem with my hard drive? I'm preparing to re-manage my partitions so I thought it would be smart to defrag first.

Edit: After a third reanalysis, Puran Defrag and Defraggler both tell me I have only 125mb fragmentation. Just some kind of fluke I guess.

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An alternative is to use a better defragger that can do boot time defrag.

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I agree... some defraggers cough cough "windows" cough cough, aren't as robust or as good. – KronoS Aug 27 '10 at 23:31

Maybe you've not enough free space in each partition. And make sure to run Defraggler before the OS start if it's able to.

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I am not aware of Defraggler having the capability to run off a live cd. And I do not understand what you mean by, "Maybe you've not enough free space in each partition." – Thomas B. Aug 27 '10 at 19:33
When Defraggler tries to defragment your partitions he does a kind of housekeeping so it needs to move your data within your partition to create the largest possible contiguous empty space. So it needs some room to make these operations: more room means more chances to success. You may want to read: – cYrus Aug 27 '10 at 20:05

Certain files such as those currently in use and certain operating system files can't be moved (or not, at least, while the system is running). A couple of examples might include device drivers and the swap file (if present). I'm fairly comfortable saying that you'll probably never get the fragmentation percentage down to 0.

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Do you know of a defragging program that will run outside of windows? Like on a live cd? – Thomas B. Aug 27 '10 at 20:24
Very, very strange. I just re-analyzed my hard drive with Puran Defrag like CGA suggested, and it told me I have only 125 mb fragmentation! I then went back into defraggler and it also said the same thing. I don't understand it, but oh well. I'm not complaining. – Thomas B. Aug 27 '10 at 22:46

I do a defragmentation using Diskeeper on the 1st of every month, and this time my hard drive wasn't too fragmented but it was kind of fragmented so I ran the defrag and then after it was done it was still a little bit fragmented...when I used to do would get 100% defragmented. I think it happens when it gets TOO fragmented!

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Its probably the restore files. Turn off system restore ( have an image available just in case) Run defraggl;er and turn restore back on

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The MFT cannot be defragmented while the volume is in use. Neither can files that represent some registry files, the pagefile, C:\hiberfil.sys.

You need a defragmentation program that can run before Windows starts (like chkdsk does) to do that.

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