Thanks for that, Husky. I also found a few discussions on the Opera community forum, but nothing definitive. Some of my own security software also generates false positives for what I think are very common programs - WS_Ftp and the like. It's a very complex world to program for.
It's really weird, the browser opens with my homepage and I can go to links from that page but when I open a new tab and enter a url, bang, "Could not locate remote server" and then nothing works whatsoever.