O&O Software has recently released a free edition of their popular defragment software, O&O Defrag. The free edition comes without any usage limitations and includes the necessary set of tools needed to optimize system performance.
Some features are missing in the free edition which is available in the paid version of O&O Defrag. The free edition supports only 2 defragmentation methods and lacks features like boot-time defragmentation, automatic background optimization and support for solid state drives. For a complete comparison between the free and professional edition see the image attached below.
O&O Defrag Free vs Professional Edition Comparison :
Supported OS :
Windows XP, Vista and Windows 7 (Both 32-bit and 64-bit)