In the last couple days, I encountered the Unity Launchpad error in Ubuntu 12.04 LTS (Precise Pangolin) Beta 1. I got the error dialog box displayed, closed it, got a blank screen, nothing there. No launchpad.
How I got into the terminal or launched the application? How I fixed it?
Launched the keyboard shortcut by pressed these keys together <Ctrl><Alt>T
Now in the terminal, I ran these commands:
~$ sudo apt-get update
~$ sudo apt-get upgrade
I thought the new updates would fix it. Still no launchpad. I typed this command at the terminal
The launchpad launched. Still some glitches. Reboot. Repeated these processes above couple times, it worked.