In the left pane of the window you need to click on the + next to HKEY_CURRENT_USER. 
Next click on the + next to Software. 
Then look for the entry of Space Sciences Laboratory, U.C. Berkeley 
Click that one to select it, then press Delete on your keyboard. 

Now we go to HKEY_LOCAL_MACHINE, click on its + to open it up. 
Click on the + next to Software. 
Look again for the entry of Space Sciences Laboratory, U.C. Berkeley 
Click it to select it, then press Delete on the keyboard.