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I can't remotely connect to the office PC, the connection is interrupted. Tell me what ports does TeamViewer use. Do I need to change my Windows firewall settings before establishing a connection?
Usually, before using TeamViewer, you do not need to change the equipment settings. For the stable operation of the program, a stable Internet connection is sufficient. Problems arise only if the firewall is set not to standard, but to increased protection.
TeamViewer uses three ports to connect to a remote device. Let’s list them:
- TCP / UDP 5938 – the main port, used by default, provides high data transfer speed.
- TCP 443 is the second most important after TCP/UDP 5938. Used to update TeamViewer and transfer data when the main port is unavailable.
- TCP 8 involves if the previous two ports are blocked. The data transfer speed is low, connection breaks are possible.
Some organizations block connections from unfamiliar devices to protect corporate information from theft. In this case, before connecting, you need to add the TeamViewer ports to the firewall exception list on a remote PC. If the connection over TCP/UDP 5938, TCP 443, and TCP 8 is not blocked, but the connection fails, then it’s not the firewall. The same errors may appear due to poor communication quality, outdated software, incorrectly selected program and antivirus settings.
