How to recover splash screen
Open the terminal and type:
sudo update-alternatives --config default.plymouth
Select the original default and then
sudo update-initramfs -u
Reboot.
If it still doesn't appear then open a terminal and type the following command:
sudo -H gedit /etc/initramfs-tools/conf.d/splash
or this command by Alt+F2
gksu gedit /etc/initramfs-tools/conf.d/splash
This file may not exist, so you may be creating it from scratch now. Enter the following content on the file you opened on the previous step:
FRAMEBUFFER=y
Close and save the file. Now, run the following command to commit the change:
sudo update-initramfs -u
Reboot and enjoy your Plymouth splash screen.
I know this is an old post, but for others who need help, here's another way, which worked for me in Ubuntu 12.04 (after I got stuck with the Lubuntu splash):
1) Open a terminal and type gksu gedit
2) Enter your password and press enter
3) Click "File" --> "Open"
4) Click on "File System" and go to /lib/plymouth/themes. Open the file "default.plymouth"
5) Make it so that the file says this:
[Plymouth Theme] Name=Ubuntu Logo Description=A theme that features a blank background with a logo. ModuleName=script [script] ImageDir=/lib/plymouth/themes/ubuntu-logo ScriptFile=/lib/plymouth/themes/ubuntu-logo/ubuntu-logo.script
6) Save the file and exit.
All done!