New user destination files access denied.

Win XP SP3 64Bit Comodo 1.04337 downloaded yesterday. I have managed to transfer folders from my external drive sourse to another external drive destination.
But whatever I try I cannot get the program to update in any mode including synchomisation.
I sometime get message unable to write file access denied. Does anyone know whats wrong?
and how to fix. Thanks TOOMBY.