STOP doing that! A crash during defragmenting is much like me pulling the rug out from under you. YOU may be hurt. My analogy is that you are placing the machines data at SEVERE RISK!
In short, there were issues with older OS's like 95, 98 and ME and Norton's defragmenter that were never resolved. I would just uninstall that program and use the supplied defragmenter.
Another issue is that some machines are aging and small hard disk errors which windows will not handle with any grace will cause this problem.
Do yourself a favor and try the supplied tools in SAFE MODE after you have assured yourself that you can lose all your data on the hard disk.
Bob
When I try to defrag with my system tool or try to defrag with norton utilities. My system crashes with a fatal error. I send it to microsoft, I get a message that it was a conflict between windows and a intel storage device. They say that they have found a solution, but I never get anything back from them that solves the problem. I have windows xp

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