Member Avatar for vuyiswamb

Good Day All

i have a Silverlight application that i have written. Tested and it works well in our internal network. Now in my company we have another server, so our Network guys open a port so that someone who is not in our network can view the website.

Now as you know Silverlight uses WCF services, i came across a problem when accessing the website from outside. You can see the home page, but now there are database work that are done (e.g) when you login , and other things that are related to the database.

"I used netstat -ano to check if really the port is open and i saw it was because it was saying "Listening" , i checked with the network guys to see if there is no firewall blocking that port and they said none"

Obviously i know that this has nothing to do with my code or my application, there is somewhere in the network settings they did not configure well.

Another thing is that when i access the WCF url from outside , i see it. I have used fidler to make sure that i am seeing the correct error here. The says

No Connection Could Be Made Because The Target Machine Actively Refused It X.X.X.X:8495

I goggled this a lot and most of the people point to security issue.

What would you advice in this regard


Thanks

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Dani AI

Generated

Thanks to for the basic connectivity pointers — here is a concise, practical checklist and a few WCF/Silverlight specifics to help anyone who runs into the same "actively refused" symptom later (and to make the cause easier to spot next time).

Start with the network path (router/NAT/firewall):

  • Confirm the external port actually forwards to the correct internal IP and port (external :84 might be NATed to internal :8495 or similar). Ask the network team for the exact port-forward rule and internal destination.
  • From outside, try a raw connect to the service port and inspect the response. Useful commands:
# from a remote machine
telnet X.X.X.X 8495
curl -v http://X.X.X.X:8495/YourService.svc

Server-side checks:

  • Verify the service is listening on the expected interface (not only on 127.0.0.1). On the host, map the port to the process and PID:
netstat -ano | findstr :8495
tasklist /FI "PID eq 1234"
  • If hosted in IIS, check the site binding (IP, port, host header). If self-hosted WCF, confirm the base address/endpoint isn’t hardcoded to localhost.
  • For HTTP-hosted services, check URL reservations and http.sys bindings: netsh http show urlacl and netsh http show iplisten.
  • Ensure Windows (or appliance) firewall has an inbound rule allowing the service/process and correct port.

Silverlight/WCF notes:

  • If calls cross domains, Silverlight needs a clientaccesspolicy.xml or crossdomain.xml at the web root; without it you’ll see security failures (not a TCP “refused” — but still worth checking).
  • If using non-HTTP bindings (net.tcp), publish and open that port and enable the protocol in IIS.

Final tips:

  • Enable WCF tracing/message logging to capture server-side failures.
  • Prefer HTTPS and restrict inbound access to known IPs; never expose DB ports directly. If the thread author already fixed it, keep a short note of which change fixed the problem (NAT rule, firewall rule, binding, etc.) so others can learn the exact root cause.

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Member Avatar for hiddenben

Hi, working with WCF is a litle bit complicate, but i don´t think the problem is from wcf, is you are using wcf just to publish a website there have not to be an error there, follow those steps to check:

1.- Try to do a telnet from client machine, example: telnet xxx.xxx.xxx.xxx port where x(s) are the ip address where you have posted the website.
2.- Try to publih the website in standard port 80.
3.- Use capture sofware to see the packets. protocol http or tcp/ip like wireshark, even from mozilla you can debut any http request with live http

Member Avatar for vuyiswamb

Good Day Friend

The Problem have been resolved and your answers point to the problem.

Thanks

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