Authentication required!

I bought a brand new WD MyBook Live and the setup went OK.  I set my self up as admin on the drtive and entered my password.

I have a windows 2008 server that I am trying to copy files from to my WD MyBook Live and everytime I try I have to authenticate yet I can’t find anywhere were I can type in the password to authenticate.  (I am on a MAC running mavericks)

Any help would be appreciated as I realluy did think that it would be an easy process.

go on the devices web UI page and make sure that your user account has access to the share.