Ubuntu Dash is blank. How do I get the apps back? [duplicate]
If the applications stoped showing in Unity Dash than you should first kill this daemon:
pkill -f unity-applications-daemon
The next step go to your /home directory and press CTRL+H to reveal hidden files. Than search for .cache folder open it and delete software-center catalog.
Afterwards restart the applications daemon:
/usr/lib/unity-lens-applications/unity-applications-daemon
If you still don't have anything in the Dash than press ALT+F2 (to bring up run command dialog) type there:
unity --replace
and run that command. If that didn't do the trick try rebooting computer.