Ubuntu – Program won’t start from launcher

So I had that problem after I did some clean up on my desktop (too many files!)
usually I just add the program to the launcher by right click>lock to Launcher
but someone the program that I’ve already have does not load when I click, and unlock then locking it back does not seem to work

the program was Cooja but it should be the same for any program

so a work around is by opening the terminal (ctrl + t)
adila@adila:cd ~/.local$ cd share/applications/
adila@adila:~/.local/share/applications$ ls
mimeapps.list se-sics-cooja-gui.desktop
adila@adila:~/.local/share/applications$ gedit se-sics-cooja-gui.desktop

that will open the file
[Desktop Entry]
Encoding=UTF-8
Version=1.0
Type=Application
Name=Cooja: The Contiki Network Simulator
Icon=se-sics-cooja-gui.png
Path=/home/adila/Desktop/contiki-2.7/tools/cooja/build
Exec=/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java -Xmx512m -Duser.language=en -classpath /home/adila/Desktop/contiki-2.7/tools/cooja/build:/home/adila/Desktop/contiki-2.7/tools/cooja/lib/jdom.jar:/home/adila/Desktop/contiki-2.7/tools/cooja/lib/log4j.jar:/home/adila/Desktop/contiki-2.7/tools/cooja/lib/jsyntaxpane.jar se.sics.cooja.GUI
StartupNotify=false
StartupWMClass=se-sics-cooja-GUI
OnlyShowIn=Unity;
X-UnityGenerated=true

the important part is where the file is at
I accidentally misplaced the file

so you can either change the classpath or delete the whole thing and start over by unlock, then locking it back on the launcher (run it as usual from the terminal or how ever you do it)

a good explanation of the local and global directory is at http://askubuntu.com/questions/418295/chrome-wont-start-from-the-launcher