Try disabling the Firewall and see if it's due to Norotn or not.
ok i house sit for these people over the summer and they allow me to use their computer with their internet. They have a dell running win xp home and use comcast internet. They have norton antivirus and norton internet security. my issue is that i can only run internet explorer to use the internet; no outside programs are accepted. For instance, i downloaded and tried to use fire fox but i was unable to load any web page. Is this being blocked by a firewall forcing the use of internet explorer?

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