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After upgrade to Quantum, All websites cause a "Server Not Found" error

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  • Last reply by Shadow110

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I was using Firefox 56 yesterday with no issues. It apparently upgraded in the background to Quantum, and now it won't connect to any websites. I CAN connect to internal pages (like my printer and router), but any external pages generate a "Server Not Found" message.

I'm on Mac 10.13.1, and both Chrome and Safari connect with no issues.

I've:


Again, the other browsers work fine. It's just Firefox Quantum. (And I tried downloading and installing 56.0.2, which worked perfectly yesterday, and now it does the same thing.

I was using Firefox 56 yesterday with no issues. It apparently upgraded in the background to Quantum, and now it won't connect to any websites. I CAN connect to internal pages (like my printer and router), but any external pages generate a "Server Not Found" message. I'm on Mac 10.13.1, and both Chrome and Safari connect with no issues. I've: * Deleted and reinstalled Firefox * Deleted the Library/Application Support/Firefox folder and Firefox, emptied the trash and reinstalled from a new download * Followed the instructions (here: <https://support.mozilla.org/en-US/kb/server-not-found-connection-problem#w_firefox-cannot-load-websites-but-other-browsers-can>) to set the browser to "No Proxy" (like my other browsers), turned off DNS Prefetching and disable IPv6 * Performed a "Firefox Refresh" Again, the other browsers work fine. It's just Firefox Quantum. (And I tried downloading and installing 56.0.2, which worked perfectly yesterday, and now it does the same thing.

Chosen solution

And there we go.

Turns out my VPN (PIA) was blocking it.

I hadn't changed any settings in switching, but with the VPN off, Firefox is working again.

Read this answer in context 👍 2

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Chosen Solution

And there we go.

Turns out my VPN (PIA) was blocking it.

I hadn't changed any settings in switching, but with the VPN off, Firefox is working again.

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Hello,

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