Core installation causes Arduino IDE boot crash

Hi Guys,

I have recently tried to install the Arduino Due core on my copy of the IDE (1.6.5) and it got most of the way through before failing. I now am not able to boot the IDE as it gets to the 'Initialising Packages' phase and crashes.

I have tried multiple times uninstalling and reinstalling with no success. I have also tried the version of the IDE that does not require installing and the same error occurs. I have tried rebooting the system and trying again but again, to no avail.

Any help would be much appreciated,

Edward