Disable ScheduledDefrag "Windows 7"

By default on Windows 7, Scheduled task for Defragmenting local HDDs is enabled to run Every Wednesday at 01:00 AM.  

You can disable this task using following command:

schtasks /change /tn "microsoft\windows\defrag\ScheduledDefrag" /disable

If you want to disable ScheduledDefrag to the Domain computers in your company then create a BAT file and include it as computer based GPO logon script.
After applying this GPO to the target computer run  taskschd.msc. The status of  ScheduledDefrag is disabled.