Norton Security Suite caused more problems than it was worth with Tiger 10.4.11 even after help from Norton. Uninstalling it and Installing Intego's Virus Barrier along with Net Barrier (now in a combination) worked fine. I've used Intego's software since 2005 when Norton's product was also inadequate for my use.
Comcast doesn't support Mac very well, especially with antivirus stuff. You can look at the format on this forum and see that it is totally Microsoft stuff. In the future ignore anything that relates to anti spam, viruses, etc. They do NOT, DO Not support Mac. Use what you can. Stick to the usual stuff and don't get hooked into anything EXTRA. You'll only get disappointed.