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What is UltraDefrag?

UltraDefrag is an open source disk defragmenter for Windows NT 4.0 and later operating systems. It makes use of the same defragmenting API used by many other windows defrag utilities, both open and closed source. 
However, UltraDefrag has many features that make it unique. 
The first is that it has a kernel mode driver that does most of the work. 
The second is the ability to run the application at boot up time in a manner similar to chkdsk. This allows for faster defragmentation time and the ability to defragment all files including system files. It can also defragment single file or directory and can even generate a list of all fragmented files. 
The program is available for both 32bit and 64bit version of Windows.

 
UltraDefrag has the following features:

Very fast defragmentation, the work is done via a kernel mode driver which has an optimal defraging algorithm.

Single File or Directory defragmentation ability. Select any File or Folder in Explorer and choose the appropriate context menu item to defragment them.

Debug logging feature - Program writes debugging information to %windir%UltraDefraglogs directory. That means if your windows is installed in drive "C" and directory name is "Windows", then logs can be found in C:/Windows/UltraDefrag/Logs.

Very small engine written in pure C.

PortableDefrag can be installed on demand which can be carried around in USB storage devices and used without any installation.

Nice graphical interface - compact and functional.

Safety, because the file moving is accomplished with Microsoft's own Defrag API.

Simple to use.

Set program's filter to exclude unwanted files and folders from the analysis.

Ability to generate html reports of fragmentation status.

Ability to include/exclude files based on simple filters.

Native x64 support.

Free: Distributed with full source code under the GNU General Public License.

Many GUI translations were made:
Catalan, Chinese (Simplified), Chinese (Traditional), Dutch, French, German, Greek, Italian, Portuguese, Slovak, Slovenian, Czech, Korean, Latvian, Polish, Portuguese (Brazilian), Spanish (AR)

Scripting support for boot time interface. Now you can do anything with your drives during the Windows Boot Process.

Portable Version also available.



Changelog:


Debug logging feature added - Program writes debugging information to %windir%UltraDefraglogs directory. That means if your windows is installed in drive "C" and directory name is "Windows", then logs can be found in C:/Windows/UltraDefrag/Logs .

Single File or Directory defragmentation ability added. 
Now you can select any File or Folder in Explorer and choose the appropriate context menu item to defragment them.

Console and native programs are much faster now. 
Set program's filter to exclude unwanted files and folders from the analysis.

G.U.I program was translated into the following languages:
Czech, Korean, Latvian, Polish, Portuguese (Brazilian), Spanish (AR)

G.U.I design was improved.

Two different driver versions (for NT4 and later systems) were replaced
by one universal os version independent driver.

Installer was highly optimized.

Many Important 64bit (x64) version bugs were fixed and well tested.