Can't use new My Book on Mac

WD Legacy Products Other Network Drives
1

Hi, I have just bought a new My Book Studio Edition 2 and I am not happy with it. I am using it on my Mac OS X (Leopard). To put files on the drive, it asks for my password and to delete them off the drive it also asks for my password but then tells me I don’t have authorisation. How can I disable this feature or is there at least a workaround?

Cheers