I have a PC from work on my home network (which is just a wireless router, 2 macs, and a "SimpleShare" NAS device). It is set up to login to a Domain and not a Workgroup. The NAS just has default settings (wg "WORKGROUP"). Now, I can pull up \\SimpleShare (the NAS) and access the shared folders, except for one which I have password protected. When I try to access that share, I get this authentication window: The User Name field is unhelpfully grayed out. Why won't it let me enter the username?