This tutorial will explain How to change the boot splash screen image for 10.04
Open the terminal and run the following commands
sudo cp /usr/share/applications/gnome-appearance-properties.desktop /usr/share/gdm/autostart/LoginWindow
Then logout, and you’ll see an Appearance window pop up. Change it to how you prefer it, then close it and login as usual.
When you have logged in after finishing the customizing, run this command to prevent the Appearance window from opening at the GDM screen every time.
sudo unlink /usr/share/gdm/autostart/LoginWindow/gnome-appearance-properties.desktop
This tutorial is garbage and does nothing, the question is how to change the log on screen with 10.04 not the theme, you could avoid this process by right clicking and clicking change background.
You can do some level not like 9.04 .you can change the background image and few things .use Ubuntu Tweak latest this has few capacity to change the images
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