If it is running, best to leave it and leave the computer and come back later. I wouldn't attempt to cancel it. If this is a laptop, ensure the mains supply is plugged in. Depending on the size of the hard disk and the speed of the computer, it could take a long time.
But when it is done, do you need to keep it running? Absolutely not. In fact, now you have run it once, it won't be needed for another 6 months to a year, if at all.
Defragging is one of those issues that has grown up over the years as an 'essential task'. It is not, unless you are constantly installing then uninstalling files, moving multiple files around, and deleting files all the time.
But for normal use modern computers it is hardly ever needed.
Mark
Hi there!
I got some info. today, from another site, about this program, and Cnet gave it high praise, so I installed it.
I am a "Newbie" with a Laptop equipped with Windows Vista Home Premium.
I see it going through everything, and am just wondering, how long does it take to go through everything, and, do I need to keep it on here?
Is there any harm to having this program running?
Thanks so much everyone!

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