Smart Defrag is from iobit software. CNET does not create, release, or endorse software... it just provides a safe place to download software from.
defraggers usually can't work properly with low diskspace and some cause problems if you continually interrupt them. if you have a problem with Smart Defrag, you should post your issue here or, better yet, at iobit.com's support center or forums.
Beware this program, DO NOT DOWNLOAD OR USE!
This program just fatally screwed up my computer.
It fragmented the drive over 4 times worse than it was before downloading and running CNET's SMART DEFRAG program.
Thanks for the help CNET, will never download anything else from you, have been computing for over 20 years and never had anything screw up as bad as this program!
WARNING!!! DO NOT USE THE SMART DEFRAG PROGRAM!