Are you using default theme - Ambiance? Then panels should not be black. I wanted that you change back to system theme to check if problem is in custom style. I know one person who had problems with transparent panels. Problem disappeared when he changed settings back to system theme.
Transparency does not work fully anyway so I would suggest to use system theme for now. I have plans on fixing panel background, but that probably wont happen this year - so background probably will be broken even in ubuntu 15.04 version. :( Reinstall wont solve anything. You can try to reset gnome-panel configuration (see accepted answer): http://askubuntu.com/questions/125662/how-to-reset-gnome-panel NOTE: It will remove all your customization to panel and will reset to default. Then try if now gnome-panel starts every time you login. If all good try to start customize it step by step: 1) Add custom launcher - do several reboots. 2) Try to customize panel style - do serveral reboots. This way you will find what part is causing problem or you will be lucky and problem will disappear. -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-panel in Ubuntu. https://bugs.launchpad.net/bugs/1380095 Title: Gnome Fallback[s] don't work in 14.04. Work once ONLY if reinstalled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-panel/+bug/1380095/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs