GrowlHelperApp does not exist

Please excuse my ignorance but I am getting the following output and unable to run the script. Can you help?

GM19135:~ me$ defaults write com.Growl.GrowlHelperApp GrowlLoggingEnabled -int 1
GM19135:~ me$ sudo killall GrowlHelperApp
No matching processes were found
GM19135:~ me$ open /Library/PreferencePanes/Growl.prefPane/Contents/Resources/GrowlHelperApp.app
The file /Users/me/Library/PreferencePanes/Growl.prefPane/Contents/Resources/GrowlHelperApp.app does not exist.
GM19135: me$ chmod +x /usr/local/bin/SpotifyNowPlayingAgent
GM19135:~ me$ launchctl load -w ~/Library/LaunchAgents/com.spotify.NowPlayingAgent.plist

Today I rcvd all the same messages as above, but says already loaded. Any insight?

GM19135:~ me$ launchctl load -w ~/Library/LaunchAgents/com.spotify.NowPlayingAgent.plist
com.spotify.NowPlayingAgent: Already loaded