Originally scheduled to appear among the other products in this comparative review, O&O Software's O&O Defrag (OOD) 8.0 ran into problems in my testing. I can't rule out the possibility that something is wrong with the configuration of my test server, but at the same time, it's worth noting that the other three products tested successfully.

After manually installing OOD's Server edition to a freshly restored Windows Server 2003 installation, I ran my standard defragmentation tests against the 80GB volumes with 5 percent and 20 percent of free space. In each case, OOD reported that the defragmentation progress halted after running to 33 percent completion. Task Manager reported that the OOD service was using a steady 50 percent of available CPU—likely 100 percent of one of the two hyperthreading processors.

OOD gave me an additional software module to help diagnose the problem. After I installed this module, defragmentations ran to completion but the resulting disk was corrupted. Chkdsk reported numerous errors, and using the Chkdsk /f (fix) option resulted in a disk with many files missing. I was able to run a successful defragmentation on an older Windows 2000 Professional system, defragging a 75GB disk with about 35 percent free space. At this writing, I'm still working with O&O to resolve the problem.

In spite of my test-bed failures, OOD might offer compelling features for your environment. It's a competently designed system. I particularly like the flexibility to create my own groups of computers independent of the AD groupings, as well as the simplicity of the product's one-button defrag capability.