Possible cause 1 of 5:
A firewall or an anti-virus program is blocking browser access to the internet
You may need to change some settings if you've installed third party security software on your computer. If your firewall or anti-virus program isn't correctly set up, you can't browse the internet.
What you need to do
Open your firewall or anti-virus program and check that your browser is allowed to establish a connection to the internet.
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