I would not run IPv6 unless you have to. I don't know that it's a problem, but it would not be surprising if you must only run one or the other.
The three PC's need to be on the same network. Win7 networking with respect to home, work, public is a bit of a mystery, but make sure they are on the same network, as closely configured as possible.
Try using MC's DLNA components first, then going on to Windows DLNA after you've established that MC works.
Everything is on a 192.168.123.xxx network. The network consists of a Dlink DIR-655 gigabit wireless n router and a Dlink 8 port gigabit switch.
Win 7 machine is connected directly to the DIR-655 at gigabit speed.
Vista 1 machine is connected to the switch at gigabit speed.
PS Audio Perfectwave DAC appliance is connected to the same switch at 100 Mb speed.
Vista 2 machine is connected to wireless N at n speed.
I agree, the 'Home, Work, Public' stuff does not make much sense. The Win 7 machine has a fixed IP address set. MC15 DLNA is setup and has been setup from back when I had an XP machine instead of the 7 machine. Windows media Player is not used and media sharing has been setup with defaults to allow all. Did not seem to matter whether windows streaming/sharing was turned on or not.
I am not even sure how you would setup Windows DLNA but I can say that when you go to Windows Explorer and click on 'Network' all of the media devices on the network (including some not mentioned here) appear there, just not in MC15.
I have taken the whole network down (powered off) and brought everything back up. Here are the results:
The win 7 machine consistently sees the other 2 MC15 machines (the Vista ones) and the PS Audio appliance.
The Vista 1 machine (hardwired gigabit) is consistently seeing all MC15 machines and the PS Audio appliance.
The Vista 2 machine (wireless n) is consistently seeing the Vista 1 machine and the PS Audio appliance, but is intermittently seeing the Win 7 machine. I would blame that on the wireless connection except for the fact that it see the Vista 1 and PS Audio consistently. I don't know, you just gotta love Windows.
Just so you know all 3 machines are getting their music from a 6 TB Linux server that is hooked into the same switch as the Win 7 machine and none of the machines have any problem playing music perfectly from that server. Go figure??