linuxmint xserver crashes on logout

Hi

I installed centrify Express with openssh on a Linux Mint 17.3 with NVidia drivers.

Ssh login works fine.

Right after booting the machine show login screen no problem, but when I logout after a session xserver and mdm (the greeter) crashes and I'm not able to restarted.

I will collect more info, but so far I have not seen any error or event that catches my attention

Thanks

Max