Firewall blocks streaming of video content to TV using DLNA

I have a Samsung TV and a PC using Windows 7 Ultimate. Both are connected through a home router. When I enable the built in Windows 7 firewall, I am no longer able to stream content over DLNA from the PC to the TV. If I disable the firewall, everything works. I am using the built in Microsoft firewall. I would like to enable the firewall and have DLNA streaming but don't know how to...