I'm far from being an expert as well, but I try.
Anyways, my best guess is that the installer didn't over write the older files. Try dropping down to runlevel 1
and running the installer again. Make note of any errors you get.
“Gosh, you've... really got some nice toys here.”
LinuxMint 15 (Olivia) XFCE 64bit • AMD Sempron 3100+ • 2GB DDR 400 • NVidia GT240 512MB