Attempting a new installation of Ubuntu 12.04 LTS on what was a dual boot Windows 7 and Ubuntu 12.04 LTS laptop ( Sony intel i3 core 64 bit with 500GB HDD). I followed the following procedure Install Ubuntu • has at least 4.4 GB available, is connected to the internet, download updates while installing and install this third-party are all ticked this time • I chose the Erase disk and install Ubuntu option ( since I want to have only Ubuntu 12.04 LTS operating system in my disk) Now shows The entire disk will be used • 501GB free disk

I clicked the install now button. All data copied to the hard drive ( it was copied OK), askes for location, keyboared layout, and who are you. Started to install the Ubuntu 12.04 operating system. After some minutes, I got a report Installation failed, the installer encountered an unrecoverable error. A desktop session will now be run so that you may investigate the problem or try installing again. So, Please give me simple advice on how to proceed. Thank you