I pinged our KDE guru. In the meantime: do you see anything in the file .xsession-errors in your home directory? (It's a hidden file). Can you please attach it here?
Can you login at a text console (Ctrl+Alt+F1)? -- Problem with login in!! https://launchpad.net/bugs/53518 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
