The connection does not come about (firewall, proxy, port 443)

What it is for

BrowserDesk needs only one connection to the outside: to the relay over port 443 — the same one every encrypted website uses. A VPN is not needed. In corporate networks, however, a firewall, a proxy or an inspection of encrypted connections often stands in the way. The built-in network test shows step by step where it gets stuck.

What you need

• The BrowserDesk program on the computer that does not get through (on your side or on the device).
• For releases in firewall or proxy: your IT.

How to do it

1. Does the computer have internet at all? Open any website. Without internet nothing below helps.
2. Read the sentence. - "Zeitüberschreitung — der Relay hat nicht geantwortet. Besteht eine Netzverbindung?" (timeout — the relay did not answer) or "Der Relay ist nicht erreichbar. Besteht eine Netzverbindung?" (the relay is not reachable) — your computer does not reach the relay. Continue with step 3. - On the device, in the box of the card Ihr Desktop (Your desktop): "Keine Verbindung zum Server. Prüfen Sie die Internetverbindung und die Relay-Adresse unter Einstellungen → Netzwerk." (no connection to the server) — the device does not reach the relay. Run the test on the device.
3. Start the network test. Einstellungen › Netzwerk (Settings > Network) → card Netzwerktest (Network test) → Test starten (Start test). The test checks name resolution, port 443, certificate, HTTPS and the connection used for brokering, one after another (KB: Network diagnostics). Read the first line that is not OK:

| Line in the test | Meaning | Remedy | |---|---|---| | "Proxy (Windows-System)" with a warning | A proxy is set in Windows — but BrowserDesk does not use it by itself and connects directly. | Enter the proxy in BrowserDesk (step 4). | | "DNS-Auflösung" (DNS resolution): "fehlgeschlagen" (failed) | The relay's name cannot be resolved. Often the corporate DNS blocks the domain. | Ask IT to allow the relay address. | | "TCP 443": "kein Durchgang" (no passage) | The firewall does not let port 443 through to the relay or requires a proxy. | Release by IT, or enter the proxy (step 4). | | "TLS-Zertifikat" (TLS certificate): "NICHT vertrauenswürdig" (NOT trusted) | Almost always a corporate proxy inspects encrypted connections (SSL inspection). | Ask IT to exempt the relay address with port 443 from this inspection. | | "WebSocket /ws": "fehlgeschlagen" (failed) | A proxy drops the persistent connection BrowserDesk uses for brokering. | Ask IT to allow the relay address in the proxy. |

1. Enter the proxy. Einstellungen › Netzwerk → card Proxy → mode Manuell (manual): "PROXY-HOST", "PORT" and, if needed, user and password (KB: Configure a proxy). System takes the proxy settings from the environment variables. An HTTP proxy is supported.
2. Check the relay address. The same view shows "RELAY-ADRESSE" (relay address). For browserdesk.de it is wss://browserdesk.de:443, for an own relay its address (C6).
3. Create the report for IT. Diagnose exportieren (Export diagnostics) creates a report — as a file and in the clipboard. You can send it to your IT or to us.

How you know it worked

• In the Netzwerktest all lines are OK.
• The connection comes about; on the device it says "Bereit" (ready) under Erreichbarkeit (Reachability).

What the other side sees

Nothing. As long as the connection is not up, the person at the device notices nothing.

Good to know

• For IT, in short: allow outbound TCP port 443 to the relay address, do not send this address through SSL inspection and do not drop the WebSocket connection (upgrade).
• Picture and sound take the direct path when possible. If a network blocks the direct path, the relay carries the encrypted data over port 443 as well. With a proxy this always runs through the relay.
• The Windows proxy is not taken over. Even if browsers get through the proxy, it must be entered in BrowserDesk.

If it does not work