After manually applying or downloading the hack, you’ll have a new item on the right-click menu for your drives…
Manual Registry Hack
Open up regedit.exe through the start menu search or run box, and then browse down to the following key:
HKEY_CLASSES_ROOT\Drive\shellCreate a new key under shell called “runas”, and then set the (Default) value to “Defragment”. If you want to hide this menu item behind the Shift key right-click menu, then add a new string called Extended with no value.
Next, you’ll need to create a key called “command” and set the default value to the following, which is the command to run defrag with the default options but show verbose output.
defrag %1 -v
You can alternately choose from one of the other defrag switches here if you’d like.
Downloadable Registry Hack
HowToGeek provides a downloadable registry hack to do all of this for you. Simply download, extract, and double-click on either AddDefragToDriveMenu.reg (for the regular menu) or AddDefragToExtendedDriveMenu.reg (to hide behind the Shift key). There’s also an included removal script that will remove either one.