Keyboard shortcut for Service in OS X doesn't work

I just wrote a script through Automator to make a keyboard shortcut under the title "New Finder Window Home":

on run {input, parameters}

    tell application "Finder"
        activate
        make new Finder window to home
    end tell

    return input
end run

When I run the script from Automator, the Finder opens my home tab. Then I checked "New Finder Window Home" from System Preferences > Keyboard > Keyboard Shortcuts > Services and assigned ControlOptionCommandSpace as the shortcut.

Unfortunately, the shortcut is not working! Any suggestions?

Did you change the input type from selected text to no input?

If it's not that, there is also a bug on 10.7 and 10.8 where the shortcuts for Automator services don't always work until you hover over the services menu from the menu bar. It doesn't affect just new services, so it often makes Automator services unusable.