I am using Diskeeper 7. When this was installed it automatically replaced the built in XP defrag program - that is, when I click on start/all programs/system tools/Disk defragmenter it launches Diskeeper 7. The defrag program that comes with Windows XP is a much scaled down version of Diskeeper. Are you sure it was the MS defrag than ran in safe mode? It might well have been Diskeeper Lite.