I googled your error message, zro, and it seems to be a pretty common problem with no one single answer. Some times they just start working, other times people have blamed spyware doing some dns hijacking of your browser, and other times it is attributed to the private corp dns servers being used to block employees from surfing the web on the bosses dime. But I do have a couple of suggestions.
1. Open a command window on your computer and type in "ipconfig /flushdns" without the quotes. This will clear up old caches that windows makes but I don't really thing this is going to work in your case.
2. This is the big gun and guaranteed to work in almost any case. Navigate to C:\winnt\system32\drivers\etc\ and there you'll see your hosts file, without an extension. Right click on it and open it with Notepad. at the end of it, on a line by its self, type in "216.32.78.34 topguntrading.net" again, without the quotes and save the file. This will bypass your corp dns and you will go straight to the site.
