The app stays in “Connecting” mode, “Network error. Please try again” or “Unable to connect to service. Please check your network connection and try again. Please try again” error If the error times out, check your network connection, network firewall settings, or web security gateway settings.

Note : Check the network connection to open the browser, Https://Zoom.Us to please make sure that you can access.

The content of this article is as follows.

Zoom firewall rules
- Zoom Phone firewall rules
- Zoom website firewall rules
- Firewall rules for certificate validation
- Additional IP range
Proxy server
Firewall rules for other Zoom services

Zoom firewall rules

Refer to the following table to configure the network firewall. The following rules should be applied to outbound traffic. Zoom communicates with the destination port it receives when the client connects. The firewall must be configured to allow these return connections.

protocol	port	sender	address
TCP	80、443	All Zoom clients	*.zoom.us
TCP	443、8801、8802	All Zoom clients	IPv4: 3.7.35.0/25 3.21.137.128/25 3.22.11.0/24 3.23.93.0/24 3.25.41.128/25 3.25.42.0/25 3.25.49.0/24 3.80.20.128/25 3.96.19.0/24 3.101.32.128/25 3.101.52.0/25 3.104.34.128/25 3.120.121.0/25 3.127.194.128/25 3.208.72.0/25 3.211.241.0/25 3.235.69.0/25 3.235.82.0/23 3.235.71.128/25 3.235.72.128/25 3.235.73.0/25 3.235.96.0/23 4.34.125.128/25 4.35.64.128/25 8.5.128.0/23 13.52.6.128/25 13.52.146.0/25 18.157.88.0/24 18.205.93.128/25 50.239.202.0/23 50.239.204.0/24 52.61.100.128/25 52.81.151.128/25 52.81.215.0/24 52.202.62.192/26 52.215.168.0/25 64.125.62.0/24 64.211.144.0/24 65.39.152.0/24 69.174.57.0/24 69.174.108.0/22 99.79.20.0/25 101.36.167.0/24 103.122.166.0/23 111.33.115.0/25 111.33.181.0/25 115.110.154.192/26 115.114.56.192/26 115.114.115.0/26 115.114.131.0/26 120.29.148.0/24 129.151.0.0/19 129.151.40.0/22 129.151.48.0/20 129.159.0.0/20 129.159.160.0/19 129.159.208.0/20 130.61.164.0/22 134.224.0.0/16 140.238.128.0/24 140.238.232.0/22 144.195.0.0/16 147.124.96.0/19 149.137.0.0/17 152.67.20.0/24 152.67.118.0/24 152.67.152.0/21 152.67.168.0/22 152.67.180.0/24 152.67.184.0/22 152.67.240.0/21 158.101.64.0/24 158.101.184.0/22 160.1.56.128/25 161.189.199.0/25 161.199.136.0/22 162.12.232.0/22 162.255.36.0/22 165.254.88.0/23 168.138.16.0/22 168.138.48.0/24 168.138.56.0/21 168.138.72.0/24 168.138.74.0/25 168.138.80.0/21 168.138.96.0/22 168.138.116.0/22 168.138.244.0/24 170.114.0.0/16 173.231.80.0/20 192.204.12.0/22 193.122.16.0/20 193.122.32.0/20 193.122.208.0/20 193.122.224.0/20 193.122.240.0/20 193.123.0.0/19 193.123.40.0/21 193.123.176.0/20 193.123.128.0/19 193.123.168.0/21 193.123.192.0/19 198.251.128.0/17 202.177.207.128/27 204.80.104.0/21 204.141.28.0/22 207.226.132.0/24 209.9.211.0/24 209.9.215.0/24 213.19.144.0/24 213.19.153.0/24 213.244.140.0/24 221.122.88.64/27 221.122.88.128/25 221.122.89.128/25 221.123.139.192/27 IPv6: 2620:123:2000::/40
UDP	3478、3479、8801 – 8810	All Zoom clients	IPv4: 3.7.35.0/25 3.21.137.128/25 3.22.11.0/24 3.23.93.0/24 3.25.41.128/25 3.25.42.0/25 3.25.49.0/24 3.80.20.128/25 3.96.19.0/24 3.101.32.128/25 3.101.52.0/25 3.104.34.128/25 3.120.121.0/25 3.127.194.128/25 3.208.72.0/25 3.211.241.0/25 3.235.69.0/25 3.235.82.0/23 3.235.71.128/25 3.235.72.128/25 3.235.73.0/25 3.235.96.0/23 4.34.125.128/25 4.35.64.128/25 8.5.128.0/23 13.52.6.128/25 13.52.146.0/25 18.157.88.0/24 18.205.93.128/25 50.239.202.0/23 50.239.204.0/24 52.61.100.128/25 52.81.151.128/25 52.81.215.0/24 52.202.62.192/26 52.215.168.0/25 64.125.62.0/24 64.211.144.0/24 65.39.152.0/24 69.174.57.0/24 69.174.108.0/22 99.79.20.0/25 101.36.167.0/24 103.122.166.0/23 111.33.115.0/25 111.33.181.0/25 115.110.154.192/26 115.114.56.192/26 115.114.115.0/26 115.114.131.0/26 120.29.148.0/24 129.151.0.0/19 129.151.40.0/22 129.151.48.0/20 129.159.0.0/20 129.159.160.0/19 129.159.208.0/20 130.61.164.0/22 134.224.0.0/16 140.238.128.0/24 140.238.232.0/22 144.195.0.0/16 147.124.96.0/19 149.137.0.0/17 152.67.20.0/24 152.67.118.0/24 152.67.152.0/21 152.67.168.0/22 152.67.180.0/24 152.67.184.0/22 152.67.240.0/21 158.101.64.0/24 158.101.184.0/22 160.1.56.128/25 161.189.199.0/25 161.199.136.0/22 162.12.232.0/22 162.255.36.0/22 165.254.88.0/23 168.138.16.0/22 168.138.48.0/24 168.138.56.0/21 168.138.72.0/24 168.138.74.0/25 168.138.80.0/21 168.138.96.0/22 168.138.116.0/22 168.138.244.0/24 170.114.0.0/16 173.231.80.0/20 192.204.12.0/22 193.122.16.0/20 193.122.32.0/20 193.122.208.0/20 193.122.224.0/20 193.122.240.0/20 193.123.0.0/19 193.123.40.0/21 193.123.176.0/20 193.123.128.0/19 193.123.168.0/21 193.123.192.0/19 198.251.128.0/17 202.177.207.128/27 204.80.104.0/21 204.141.28.0/22 207.226.132.0/24 209.9.211.0/24 209.9.215.0/24 213.19.144.0/24 213.19.153.0/24 213.244.140.0/24 221.122.88.64/27 221.122.88.128/25 221.122.89.128/25 221.123.139.192/27 IPv6: 2620:123:2000::/40

Zoom Phone firewall rules

Connection type: Zoom Phone

Note:
• Outbound port 390 must be open to search the company directory on your desk phone .
• To see the firewall rules for zero-touch provisioning, see the Poly or Yealink support site.

Protocol	Ports	Source	Destination
TCP	5091	All Zoom clients	8.5.128.0/24 64.211.144.0/24 65.39.152.0/24 69.174.57.0/24 103.122.166.0/23 120.29.148.0/24 147.124.96.0/19 149.137.0.0/17 149.137.25.0/24 149.137.41.0/24 162.12.232.0/22 173.231.92.0/24 173.231.94.0/24 192.204.12.0/22 209.9.215.0/24 213.19.144.0/24 213.19.153.0/24 213.244.140.0/24
TCP	390 ( see Note )	All Zoom clients	3.21.137.128/25 3.235.96.0/23
UDP	20000-64000	All Zoom clients	64.211.144.0/24 65.39.152.0/24 69.174.57.0/24 103.122.166.0/23 147.124.96.0/19 149.137.0.0/17 149.137.25.0/24 149.137.41.0/24 162.12.232.0/22 173.231.92.0/24 173.231.94.0/24 207.226.132.0/24 209.9.211.0/24 213.19.144.0/24 213.244.140.0/24

Zoom website firewall rules

Connection type: Zoom website

protocol	port	sender	address
TCP	80、443	All Zoom clients	.zoom.us .cloudfront.net

Available web browsers are Google Chrome, Safari, Firefox, Microsoft Edge, and Internet Explorer. Please refer to the Zoom Web Client for the requirements of each browser.

Firewall rules for certificate validation

Starting with Zoom Client 5.5.0 , the following URLs must be whitelisted for certificate validation :

protocol	port	sauce	First
HTTP	80	Zoom client	ocsp.digicert.com crl3.digicert.com crl4.digicert.com crl.godaddy.com certificates.godaddy.com crl.starfieldtech.com certificates.starfieldtech.com ocsp.godaddy.com ocsp.starfieldtech.com

Additional IP range

The corresponding additional IP range is listed in the following list.

Proxy server

Port 443 via https / SSL supports the proxy server. Note : This does not apply to the Zoom Phone service.

Zoom will automatically detect your proxy settings. In some cases, you may be prompted for your proxy username/password.

Note: We recommend whitelisting from zoom.us and .zoom.us proxies or SSL inspection.

Firewall rules for other Zoom services

Conference connector, etc.

Conference Connector Firewall Settings
Cloud Room Connector firewall settings
Virtual Room Connector Firewall Settings

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