Unable to install Ubuntu on VM

Hi all

Host - Ubuntun 14.04 64bit
VM to be installed - ubuntu 14.04 64bit
VirtualBox

Settings
Controller IDE -> ubuntu-14.04.2-desktop-amd64.iso

Start -> I can select "Language"
-> either clicking "Try Ubuntu without installing" or "Install Ubuntu" it died automatically after a while.

I have tried the whole afternoon without a breakthrough. Also I have checked md5sum

Pls help. Thanks

Regards
satimis