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Out of the blue, after Firefox had been working just fine for a long time, I got the following error message: "Unable to Connect. Firefox can't establish a connection to the server at www.cnn.com."

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  • Last reply by cor-el

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There were no updates or changes to Firefox. I tried changing the proxy settings and it didn't work. Then I tried to uninstall Firefox so that I could reinstall it and it won't even show up in the "Change/remove programs" window of Control Panel.

There were no updates or changes to Firefox. I tried changing the proxy settings and it didn't work. Then I tried to uninstall Firefox so that I could reinstall it and it won't even show up in the "Change/remove programs" window of Control Panel.

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Did you check your security software (firewall)?

A possible cause is security software (firewall) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process.

See:

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Thanks! It worked perfectly!

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You're welcome