To combat some recurring spammers, GTM has disabled the ability to use proxies during the registration process. You may, however, re-enable your proxy once you have gone through the registration process (your real IP will still be logged by the forum software but it will get erased over time). I'm really sorry for any inconvenience this may be to you.
If you are not consciously using a proxy, it is possible that your internet browser is doing it automatically. First and foremost, I would try using another internet browser. If that doesn't work, you can try disabling the proxy manually...
In Internet Explorer, you have to uncheck the "Use a proxy server for your LAN" check box (Tools>Internet Options>Connections>LAN settings).
In Mozilla Firefox, you have to select the "No proxy" radio button (Firefox Menu>Options>Options>Advanced>Network>Settings).
In Google Chrome, you have to uncheck the "Use a proxy server for your LAN" check box (Chrome Menu>Settings>Change proxy settings...>Connections>LAN settings).
You can find documentation for other browsers by entering your browser name followed by "enable proxy" into a Google search (obviously, you would just disable it instead of enabling it).
Another possible reason that you are getting the proxy message is that your router has been setup to automatically reroute all of your internet browsing through a proxy. If this is the case and you have access to your router, you can do a Google search similar to before but this time with the name of your router's software. If that doesn't work or you don't have access to your router than you can create an account somewhere else (like a local library).
Once again, I am really sorry for the inconvenience and I hope that you can figure it out.
Edit: This information has been added to the No Proxies During Registration page.
