Windows Media Connect can’t see my DMR: IV

You've been trying to get it to work but Windows Media Connect (WMC) doesn’t see your device, and neither does the UPnP Subsystem.  We figured that out by running the script pasted to the blog a few entries back.  What could be causing this?  Let’s get past a few basic questions before we get usual causes. If you’ve been following along the posts in order, you’ve already worked through these issues.  If not, be sure to address these first, before you continue.

Did the script give an error?  This could be caused by the UPnP Services not being started.  Go look at this post: https://blogs.msdn.com/alan_ludwig/archive/2006/01/20/515333.aspx

Does basic internet connectivity work?  Do you have a router?  Check out this post, and make sure you are testing with a “direct” and “wired” connection: https://blogs.msdn.com/alan_ludwig/archive/2006/01/18/WMCOverview.aspx

If it still doesn’t see the device the most likely cause is some kind of firewall.  For basic discovery, the ports that must be opened in the PC firewall have already been discussed here: https://blogs.msdn.com/alan_ludwig/archive/2006/01/23/516232.aspx.  But, since firewalls are the most likely problem in if you’ve gotten this far then this is a good place to review all of ports and why they need to be opened.  Here’s the full list of ports that are used by WMC: 1900 UDP,2869 TCP,10243 TCP, 10280 – 10284 UDP.

In previous posts, I’ve already covered what is done with 1900 UDP, and 2869 TCP.  Port 1900 is used for SSDP discovery.  This is where the multicast device announcements come in.  I’ve also already covered what happens on port 2869 TCP.  This is the main port for all UPnP traffic.  UPnP is basically HTML and SOAP, so essentially there is a web-server at 2869 TCP.

Port 10243 TCP is used by WMC to actually stream the media to the PC.  Basically, there is a web server on this port.  The Digital Media Receiver (DMR) uses UPnP on port 2869 to get a list of the music, video, or photos that are available.  When it is ready to play music (for example) it gets the URL of the song from UPnP and then requests it.  The port in that URL is port 10243.  The web server then streams the music to the DMR on that port.

Ports 10280 – 10284 UDP are used by Windows Media Digital Rights Management for Network Devices (WMDRM-ND) as part of the device registration process.  I’m not going to go into great detail about what they are used for since the internals of DRM are beyond the scope of this post.  But if you’d like to play-back protected music, then these ports need to be open.  Having these ports block will not interfere with discovery or even keep unprotected content from playing back. 

WMC was tested and works perfectly well with the Windows firewall. If you don’t have a 3rd party firewall, then there is no reason to go in and adjust or turn off the windows firewall.  The most you should need to do to get the windows firewall working correctly with WMC is to go into the advanced tab on the windows firewall and choose “Restore Defaults”.  After that go into the WMC User Interface (UI) and choose “Reset” under the firewall section.  If you’d like to make especially sure that it isn’t the windows firewall then you can disable it.  But, I would only do that if you are physically disconnected from the internet.  If you ever review your firewall logs you’ll see that when you are connected to the internet (especially an always-on broadband connection) you are attacked every few minutes at most. Don’t disable your firewall while you are connected to the internet.

For 3rd party firewalls you should seek help from your firewall provider.  From the newsgroups and web-forums that I visit I’ve heard a whole range of things that people had to do to get WMC working with 3rd party firewalls. I’ve heard everything from “I just opened the ports” to “I had to completely uninstall the firewall”.  Again, my advice is always the same.  If you are using a 3rd party firewall and you disable or remove it to troubleshoot WMC, don’t do that while you are connected to the internet. 

I highly recommend using firewall software.  It is critically important to have that protection.  Personally, I use the built-in windows firewall. I don’t use a 3rd party firewall on any of my computers.  My primary source of security is the firewall in my hardware router.  As a second layer of security I use the built-in Windows Firewall.  I’ve run all kinds of security scans available from reputable sources and when running in this configuration they all give me passing marks. As part of my security practices I run real-time virus detection software as well as a full scan every night (automatically scheduled while I sleep).  I also have ad ware and spyware protection. The only downside (in theory) to not running a 3rd party firewall on my computer is that I don’t control or block outgoing connections.  With the two incoming firewalls, and the ad ware and virus protection packages I don’t feel like this is a fatal security flaw.  Most folks don’t have the expertise to actually make good decisions about the validity of a particular outgoing connection so in the end I don’t think it helps much anyway.  Mostly it is just annoying to keep the list of “authorized applications” up to date and to deal with the constant pop-ups from the 3rd party firewall to authorize a particular connection or application.

That’s my whole rant on firewalls and how to troubleshoot them.  But, that isn’t the whole list of things that could be causing problems.  If your PC is a member of a domain there  a few other issues that you could run into.  I’ll cover those next time.