If you are having problems with CA accessing the web, there are a few things to be aware of.
First you cannot have two, or more, active firewalls without a conflict. Check to see if, somehow, the Windows firewall has become active. You can get there by clicking the START button and selecting Control Panel. Double-click on Security Center. If you see that the Windows firewall is on, try shutting it off. Double-check your CA Firewall settings by double-clicking the CA Security Center icon in the task bar or using the START button. If the link in the firewall section says “Restore Internet access,” click on that link.
Now see if CA can access the Internet.
Note that this applies if CA cannot access the Internet to do an update. If you cannot access the Internet, how are you reading this? Just kidding. However you got here, check your CA Firewall settings as described above.
Usually CA Firewall disables the Windows firewall when installed. If, somehow, these settings have changed, you really need to find out the cause. If you have more than one user on your computer, that is probably the reason for the messed up settings. Check your START menu and see if someone has added new programs. In some cases, a program will require you to disable the firewall to install a program. HP is famous for this.
I really do not like the idea of lowering my firewall or anti-virus to install a program. However, as a wireless user, you can turn off the wireless before proceeding with installing such a program or simply unplug your modem for DSL. Remember to disable any option of checking for updates during the install. You can do that when you restore your Internet access.
If a program wants to install and access the net without having an anti-virus program or firewall running, you should lodge a complaint with that company.
One other option to try, if using DSL—say through Qwest—is to call your local provider tech support and make sure that you modem settings have not been muffed up.
I do not know of anything else that should be preventing CA from accessing the web, save a virus or a good old-fashioned hardware problem.