Cant create new user account

I have migrated my accounts from my old G5 to new Mac Pro and they all work just fine. However when I try to create a new user account for my youngest daughter whilst everything appears to be fine on creation when i try to switch between my admin acount and her account with the correct password (less than 8 characters) all I get is the starscape with no icons, no dock, no mouse! The only way out I can find is to completely reboot the mac from the power button on the front (power down and power up again).
I have tried deleting and recreating different accounts all with the same result. The original 3 accounts that migrated all work OK.