My Computer Won't Defragment!

[:Ace:]

When I go to defragment my computer, I click "Defragment" and I get an error message which reads as follows:
"Disk Defragmenter has detected that Chkdsk is scheduled to run on the volume HDD (C:). Please run Chkdsk /f."

So, I've clicked Start, Run and typed in "Chkdsk /f" and nothing happens.

Please help!

Thank you very much!

:Ace:

[fiesata]

If you are running XP do the following
start>my computer> right click on C: drive>properties>tools > error checking- set it to run at next start up

If this does not work post back