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I'm trying to figure out why this computer can't connect to these private proxies I have. These proxies work with an IP address accept list.

So, I've looked up the IP address on the and added it to the accept list. But for some reason it doesn't work.

I have other computers using these private proxies and all of them I was able to add to accept list in the same way and they all worked.

Is it possible to tell if somehow you are behind a proxy and don't know it. Or is there a way to check for one. On, it checks for proxies, and this particular computer is says "Network Sharing Device" and other computers all say no proxy. Now that is not very specific and I have no idea what "Network Sharing Device" means, it is too vague. I mean, I know there is the router/switch, but the other computers are also the same in that they are in a private LAN.

Some things I have looked into the try to figure this out are: pinging works pinging times out. (so maybe the router is not accepting ping/icmp requests)

tracert , or any other web address only gives one result, the destination. This seems the weirdest, why only 1 result, and why the destination. What happened to the rest?

All my other networking programs works so it is obviously reaching the internet, but I'm thinking under a masked IP. (proxy) This is why the privates proxy accept list won't work because apparently it doesn't think that the IP address I provide it is correct.

Any ideas? I don't know networking that well and any real tools to troubleshoot this problem. Is there someway to get at the real IP address or maybe try to figure out if somehow that "Network Sharing Device" is actually a proxy which the ISP is filtering traffic through?

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Can you give more information? What is "your computer", is it on a home network, or at work? – benc Dec 7 '10 at 7:31
It is on a home network on my outsourcer's computer. – user62643 Dec 15 '10 at 16:55

I've figured out that the IP address is actually not what what is says on, I can tell because I finally got access to their router. I was able to use my private proxies. I still haven't figured out though what the ISP is doing to cause this issue, or what this "Network Sharing Device" is. I'm guessing the ISP is somehow filtering the some of their customers through an extra layer (proxy).

My outsourcer is changing her ISP, so hopefully that fixes the problem.

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