1) I use Tversity or Twonky as my main UPnP media servers running on a Windows PC. With these servers set up correctly I am able to connect with Media Streamer or Canola and play served "local and Internet" media on my N800. With Media Streamer I am additionally able to control playback on my Philips SL300i UPnP player connected to my Hi-Fi and TV.

www.tversity.com
www.twonkyvision.de

2) Firewalls, ports, exe's need to be correctly set up on host PC and occasionally the router to ensure visibility of media servers on your network. read the media sever software FAQ and their forum posts for more support in this area, relating to your chosen host OS.

3) OS Firewall and *.exe and Port exceptions for TVersity

With TVersity installed on my XP PC, I need to ensure that TVersities MediaServer.exe is an exception which can operate fully through XP's firewall along with setting port 41952 (UDP & TCP) as an open port through the firewall in order to get TVersity reliably visible. (I do not need to adjust my router settings, as these types of change usual relate to external WWW access, however I did need to enable routers UPnP setting?)

UPnP Canola and/or Media Streamer methods and even pointing N800 Opera Web browser (192.168.*.*:41952/lib) using "open with" build in N800 Media player methods: should all work reasonably reliably with TVersity if your network is set up correctly.

Notes:

Same overall process/method should apply to Twonky and it's related UPnP or web browser features, assuming correct *.exe and ports are allowed through Firewall.

I posted a few posts about using Media Streamer in my blog last year for the Nokia 770 which may be useful reference to new users of Media Streamer i.e. http://mikesl300i.blogspot.com/2006/...back-with.html
http://mikesl300i.blogspot.com/2006/...nokia-770.html
http://mikesl300i.blogspot.com/2006/...a-770-via.html

BTW Media Streamer expects to find UPnP Media Server(s) running on your local network and one must be selected, it will NOT directly operate/interact with the WWW.