From my experience:

scandisk - once per week --- once per two weeks,
Disk Defragmenter - when it reports less then 80% fragmentation
[it means that 20% or more of files are fragmented], this usually
results in a period of 2-4 months, depending on your disk usage.

Susan Hays wrote:
>
> Can anyone tell me how often ScanDisk and Disk Defragmenter should be run on
> my computer?

            Do you want to signoff PCBUILD or just change to
                    Digest mode - visit our web site:
                    http://nospin.com/pc/pcbuild.html