Did you try to compile tango and druntime on your own or was that a precompiled package that you've downloaded? Normally make clean and rebuild helps in that case. You could dig the sources of phobos and look if std.socket containts the symbols and then compare them with the symbols of phobos.lib. But unfortunally this is a more advanced task.
can you tell me what you've actually downloaded? I've a windows xp virtual maschine here and I'd like to replicate your issue.
