Posted 07 June 2010 - 09:18 PM
It may be true, but I don't think it would be accomplished merely by defrag. Defrag itself has no repair capability.
If Windows Defrag is being used, it is very conservative, and one of its design parameters is for there to be as far as is possible no harm to the file system if power is lost during defrag. (One reason Windows Defrag is not as fast as some people would wish.)
Normally if a system goes off during defrag, when powered up again, defrag can simply be re-started and will continue.
If the system cannot re-start, so the drive has to be transferred to another computer, that implies the file system has been damaged, and a file or files required for system boot are corrupted. If you attempt to defragment the drive in another system, defrag will detect the file system damage and require chkdsk to be run (probably on an automatic re-start for a boot-time scan). So if defrag then can successfully complete defragmenting the drive, it will be because chkdsk successfully repaired the file system.
Top 5 things that never get done: