Well thats just the problem....
I cant access the sharin preferences at all!
When I hover the mouse over the button in System Preferences, I get the message:
'Your access to this preference has been restricted'

I am quite stumped with that, like I said I am the Admin user here, so I dont really see why I should be restricted there...???

I have posted the query on the apple forums but i'm still waiting for a reply....

Thanks