Firewall or Proxy Server Setting Configuration Requirements in Zoom App

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 *
TCP 443、8801、8802 All Zoom clients IPv4:


UDP 3478、3479、8801 – 8810 All Zoom clients IPv4:


Zoom Phone firewall rules

Connection type: Zoom Phone

• 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
TCP 390 ( see Note ) All Zoom clients
UDP 20000-64000 All Zoom clients


Zoom website firewall rules

Connection type: Zoom website


protocol port sender address
TCP 80、443 All Zoom clients *

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


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.

NoteWe recommend whitelisting from and 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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