Third party firewall blocking internet access

I can not access the internet after installing, then uninstalling Norton. I deleted everything I can find on my computer from Norton, but still can not connect to internet. I get the following message: Windows confirmed that "Primary DNS Server is currently online, but is not responding to connection attempts ...this usually means that a firewall is running somewhere between he two computers".
I've tried everything I know, if someone have any ideas on how I can solve this problem, please help.