windows 2000 sp4 sharing problem

hey.
i have windows 2000 with service pack 4 installed. when i was gaming with a buddy of mine last weekend, we noticed that he was only able to copy files located at my c: drive and not from e: or f:, he could see the folders on e or f, but not open them etc. what changes did sp4 make to my windows since i can't share anything unless it's on drive c?
i was not this way then i had sp3 installed and it is becoming kinda irritating,

can anyone please tell me what i have to do to be able to share all my drives?