Cannot access secured folders on MyBook WE II

I am having the same problem.  I have a few different users with different privileges and all the folders that are not “public (full access)” I can not access them through the LAN.  It asks me for login info and it doesn’t matter what user name and password combo I use, it gives me the same error message!!!

What is the point of have user accounts and privileges if you  “ADMIN”  can’t gain access to the folder after the changes???