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why does firefox start extremely slowly when i set my firewall to allow outgoing connections only?

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When I configure my Firewall on Windows to allow outgoing connections only for firefox.exe, then Firefox hangs during startup and comes up after 30 or 60 seconds.

When I let all traffic pass through, it starts immediately.

I cannot see any listeing port in tcpview. So I wonder: Why does firefox hang when only outgoing connections are allowed?

When I configure my Firewall on Windows to allow outgoing connections only for firefox.exe, then Firefox hangs during startup and comes up after 30 or 60 seconds. When I let all traffic pass through, it starts immediately. I cannot see any listeing port in tcpview. So I wonder: Why does firefox hang when only outgoing connections are allowed?

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All Replies (5)

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Basically, Firefox is allowed to send, but not receive. Set the firewall for two-way.

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This does not explain anything.

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Firefox is a web browser. It displays what it is sent. If it does not receive anything, there is nothing to display.

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FredMcD, please!

A browser normally requires outgoing connections only, it opens a tcp connection to the web server and downloads the file. I had Firefox configured to allow outgoing connections only for many years. But something changed, some part of firefox requires "incoming" that is "listening" connections (i am not sure you know the difference between incoming and outgoing connections in firewall terms).

maybe firefox requires even some udp, do not know. please take a step back and lets wait until someone else can say something about that.

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