UltraDefrag is powerful Open Source defragmentation tool for Windows NT. It's engine is very fast, because it is created as kernel-mode driver. They are three interfaces to them: graphical, console and native. First is very useful, because it use cluster map visualization. Console is good for task scheduler, and native tool - for advanced users and programmers.
Design of the UltraDefrag is very ergonomic: no skins, no localization, no animation and so on. It's true small and powerful program!
It can be used on Windows 2000, Windows XP, Windows Server 2003,Windows Vista and all of the 64-bit editions of Windows. NT 4.0 support is currently unavailable.
UltraDefrag has the following features:
- very fast defragmentation, because engine is kernel mode driver and has optimal algorithm.
- very small engine written in pure C language.
- nice graphical interface - compact and comfortable.
- safety, because file moving is realized with special system calls.
- simple to use.
- generate html reports.
- has useful filters.
- has native x64 support.
- free: distributed with full source code under the GNU General Public License.

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