UltraDefrag is an open source disk defragmenter for Windows. It eliminates the file fragmentation problem speeding up the computers which need less mechanical work to read continuous data from disks. UltraDefrag can fix almost everything including files which are usually locked – it launches inside of the Windows boot process when most of the files are still not in use.
UltraDefrag has the following features:
• simple but efficient defragmentation algorithms
• safe environment preventing files corruption
• defragmentation of locked paging and hibernation files
• defragmentation of NTFS metafiles (including MFT) and streams
• flexible filters allowing exclusion of files by various criteria
• defragmentation of disks having specified fragmentation level
• one click defragmentation via Windows Explorer context menu
• multilingual graphical interface (over 60 languages available)
• powerful command line interface
• scheduled defragmentation (using Windows Task Scheduler)
• automatic termination when specified time interval elapses
• automatic hibernation or shutdown after the job completion
• small size of installers (about 1 MB)
• availability of portable packages requiring no installation
• full support of 64-bit editions of Windows
• granted permission to freely use and redistribute the program
UltraDefrag can defragment both FAT and NTFS disks with just a couple of restrictions:
• It cannot defragment FAT directories, because their first clusters are immovable.
• It cannot defragment master file tables (MFT), because their first 16 clusters are immovable.
However, the program tries to optimize those files placing their fragments close to each other behind the first one.
UltraDefrag can be used on Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7 and Windows 8.
Elder versions of the program (prior to v7) can be used on Windows NT 4.0 and Windows 2000 as well, with some limitations. On both those systems UltraDefrag cannot optimize master file tables and FAT directories, cannot defragment files partially and cannot handle NTFS disks with clusters larger than 4 KB. On Windows NT 4.0 the program cannot defragment NTFS metafiles and directories as well, and cannot accept short paths on the command line (like C:\PROGRA~1\SOMEFI~1.TXT).