I have installed Thunderbird version 78.13.0 in my MX Linux 21. I am having issues with this app recently because its connection with the server always gets timed out. Whenever I refresh the mails, I get this error: I could not connect to the mail server imap.gmail.com; the connection was refused. I could not figure out what happened here.
Recently, I made some changes to my firewall, in other words, iptables. There might be some issues with that. I am pasting the output of my iptables.
-P INPUT DROP
-P FORWARD DROP
-P OUTPUT DROP
-N DOCKER
-N DOCKER-ISOLATION-STAGE-1
-N DOCKER-ISOLATION-STAGE-2
-N DOCKER-USER
-N ufw-after-forward
-N ufw-after-input
-N ufw-after-logging-forward
-N ufw-after-logging-input
-N ufw-after-logging-output
-N ufw-after-output
-N ufw-before-forward
-N ufw-before-input
-N ufw-before-logging-forward
-N ufw-before-logging-input
-N ufw-before-logging-output
-N ufw-before-output
-N ufw-logging-allow
-N ufw-logging-deny
-N ufw-not-local
-N ufw-reject-forward
-N ufw-reject-input
-N ufw-reject-output
-N ufw-skip-to-policy-forward
-N ufw-skip-to-policy-input
-N ufw-skip-to-policy-output
-N ufw-track-forward
-N ufw-track-input
-N ufw-track-output
-N ufw-user-forward
-N ufw-user-input
-N ufw-user-limit
-N ufw-user-limit-accept
-N ufw-user-logging-forward
-N ufw-user-logging-input
-N ufw-user-logging-output
-N ufw-user-output
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -s 0.0.0.0/7 -j DROP
-A INPUT -s 2.0.0.0/8 -j DROP
-A INPUT -s 5.0.0.0/8 -j DROP
-A INPUT -s 7.0.0.0/8 -j DROP
-A INPUT -s 10.0.0.0/8 -j DROP
-A INPUT -s 23.0.0.0/8 -j DROP
-A INPUT -s 27.0.0.0/8 -j DROP
-A INPUT -s 31.0.0.0/8 -j DROP
-A INPUT -s 36.0.0.0/7 -j DROP
-A INPUT -s 39.0.0.0/8 -j DROP
-A INPUT -s 42.0.0.0/8 -j DROP
-A INPUT -s 49.0.0.0/8 -j DROP
-A INPUT -s 50.0.0.0/8 -j DROP
-A INPUT -s 77.0.0.0/8 -j DROP
-A INPUT -s 78.0.0.0/7 -j DROP
-A INPUT -s 92.0.0.0/6 -j DROP
-A INPUT -s 96.0.0.0/4 -j DROP
-A INPUT -s 112.0.0.0/5 -j DROP
-A INPUT -s 120.0.0.0/8 -j DROP
-A INPUT -s 169.254.0.0/16 -j DROP
-A INPUT -s 172.16.0.0/12 -j DROP
-A INPUT -s 173.0.0.0/8 -j DROP
-A INPUT -s 174.0.0.0/7 -j DROP
-A INPUT -s 176.0.0.0/5 -j DROP
-A INPUT -s 184.0.0.0/6 -j DROP
-A INPUT -s 192.0.2.0/24 -j DROP
-A INPUT -s 197.0.0.0/8 -j DROP
-A INPUT -s 198.18.0.0/15 -j DROP
-A INPUT -s 223.0.0.0/8 -j DROP
-A INPUT -s 224.0.0.0/3 -j DROP
-A INPUT -i br-44c25 -p udp -m udp --dport 16514 -j ACCEPT
-A INPUT -i br-44c25 -p tcp -m tcp --dport 16514 -j ACCEPT
-A INPUT -i docker0 -p udp -m udp --dport 16514 -j ACCEPT
-A INPUT -i docker0 -p tcp -m tcp --dport 16514 -j ACCEPT
-A INPUT -i eth0 -p udp -m udp --dport 16514 -j ACCEPT
-A INPUT -i eth0 -p tcp -m tcp --dport 16514 -j ACCEPT
-A INPUT -i wlan0 -p udp -m udp --dport 16514 -j ACCEPT
-A INPUT -i wlan0 -p tcp -m tcp --dport 16514 -j ACCEPT
-A FORWARD -j DOCKER-USER
-A FORWARD -j DOCKER-ISOLATION-STAGE-1
-A FORWARD -o docker0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -o docker0 -j DOCKER
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
-A FORWARD -o br-44c25d8fa256 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -o br-44c25d8fa256 -j DOCKER
-A FORWARD -i br-44c25d8fa256 ! -o br-44c25d8fa256 -j ACCEPT
-A FORWARD -i br-44c25d8fa256 -o br-44c25d8fa256 -j ACCEPT
-A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A OUTPUT -o lo -j ACCEPT
-A OUTPUT -o br-44c25 -p udp -m udp --sport 67:68 --dport 67:68 -j ACCEPT
-A OUTPUT -o br-44c25 -p udp -m udp --dport 53 -j ACCEPT
-A OUTPUT -o br-44c25 -p tcp -m tcp --dport 80 -m state --state NEW -j ACCEPT
-A OUTPUT -o br-44c25 -p tcp -m tcp --dport 443 -m state --state NEW -j ACCEPT
-A OUTPUT -o br-44c25 -p udp -m udp --sport 123 --dport 123 -j ACCEPT
-A OUTPUT -o br-44c25 -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A OUTPUT -o br-44c25 -p tcp -m tcp --dport 25 -m state --state NEW -j ACCEPT
-A OUTPUT -o br-44c25 -p tcp -m tcp --dport 22 -m state --state NEW -j ACCEPT
-A OUTPUT -o docker0 -p udp -m udp --sport 67:68 --dport 67:68 -j ACCEPT
-A OUTPUT -o docker0 -p udp -m udp --dport 53 -j ACCEPT
-A OUTPUT -o docker0 -p tcp -m tcp --dport 80 -m state --state NEW -j ACCEPT
-A OUTPUT -o docker0 -p tcp -m tcp --dport 443 -m state --state NEW -j ACCEPT
-A OUTPUT -o docker0 -p udp -m udp --sport 123 --dport 123 -j ACCEPT
-A OUTPUT -o docker0 -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A OUTPUT -o docker0 -p tcp -m tcp --dport 25 -m state --state NEW -j ACCEPT
-A OUTPUT -o docker0 -p tcp -m tcp --dport 22 -m state --state NEW -j ACCEPT
-A OUTPUT -o eth0 -p udp -m udp --sport 67:68 --dport 67:68 -j ACCEPT
-A OUTPUT -o eth0 -p udp -m udp --dport 53 -j ACCEPT
-A OUTPUT -o eth0 -p tcp -m tcp --dport 80 -m state --state NEW -j ACCEPT
-A OUTPUT -o eth0 -p tcp -m tcp --dport 443 -m state --state NEW -j ACCEPT
-A OUTPUT -o eth0 -p udp -m udp --sport 123 --dport 123 -j ACCEPT
-A OUTPUT -o eth0 -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A OUTPUT -o eth0 -p tcp -m tcp --dport 25 -m state --state NEW -j ACCEPT
-A OUTPUT -o eth0 -p tcp -m tcp --dport 22 -m state --state NEW -j ACCEPT
-A OUTPUT -o wlan0 -p udp -m udp --sport 67:68 --dport 67:68 -j ACCEPT
-A OUTPUT -o wlan0 -p udp -m udp --dport 53 -j ACCEPT
-A OUTPUT -o wlan0 -p tcp -m tcp --dport 80 -m state --state NEW -j ACCEPT
-A OUTPUT -o wlan0 -p tcp -m tcp --dport 443 -m state --state NEW -j ACCEPT
-A OUTPUT -o wlan0 -p udp -m udp --sport 123 --dport 123 -j ACCEPT
-A OUTPUT -o wlan0 -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A OUTPUT -o wlan0 -p tcp -m tcp --dport 25 -m state --state NEW -j ACCEPT
-A OUTPUT -o wlan0 -p tcp -m tcp --dport 22 -m state --state NEW -j ACCEPT
-A DOCKER-ISOLATION-STAGE-1 -i docker0 ! -o docker0 -j DOCKER-ISOLATION-STAGE-2
-A DOCKER-ISOLATION-STAGE-1 -i br-44c25d8fa256 ! -o br-44c25d8fa256 -j DOCKER-ISOLATION-STAGE-2
-A DOCKER-ISOLATION-STAGE-1 -j RETURN
-A DOCKER-ISOLATION-STAGE-2 -o docker0 -j DROP
-A DOCKER-ISOLATION-STAGE-2 -o br-44c25d8fa256 -j DROP
-A DOCKER-ISOLATION-STAGE-2 -j RETURN
-A DOCKER-USER -j RETURN
Is any of the settings in iptables creating the issue? What can be done to mitigate this? Please brief me about this since I have very little knowledge about it.
Edit: I tried following this link but it did not work out. Edit: I tried resetting my firewall to the default status but it did not work out either.
