====== Callers cannot connect ======

===== Nobody can connect =====

  - **Is PBDispatch running?** It must be running for new callers to reach you.
  - **Is the service on?** Open **Network > Services** in PBConfig. See [[v4:config:services|The Services screen]]. After changing a port or an on/off switch, restart the service in [[v4:dispatch:services|Service Management]] or restart PBDispatch.
  - **Is the port really open on this PC?** In a command prompt, run ''netstat -ano | findstr ":23 "'' (use your port) and look for LISTENING.
  - **Is the Windows Firewall allowing it?** See [[v4:install:requirements|Before you install]] for the ''netsh'' command.
  - **Is your router forwarding it?** Callers from the Internet need the port forwarded to this PC.

===== "Port in use" =====

Two programs cannot listen on the same port. Another program owns it. Common causes:

  * **SSH on port 22:** Windows' OpenSSH Server owns it. Stop and disable it (''services.msc'', //OpenSSH SSH Server//), or give the BBS another port. See [[v4:connect:ssh|SSH]].
  * **FTP on port 21:** the PBLink QWK hub also defaults to 21. Give one of them another port, or share one port. See [[v4:connect:ftp|FTP downloads]].
  * **Web on port 80:** another web server, such as IIS, is running.

PBDispatch writes the reason to its event log. **Tools > FTP Sessions** says "NOT LISTENING" when FTP is not open.

===== A caller is refused, or banned =====

  * **Login Guard.** Too many wrong passwords from an address ban it for a while. Look at **Tools > Login Guard > Status**. To lift the bans, use **Clear Bans**. Your own PC is never banned. See [[v4:connect:login_guard|Login Guard]].
  * **Host Filter.** The address may be on a list. A refused connection is closed silently. Find it in the log, add it to **Always allow** in PBConfig, then reload the host filter (**Dispatcher > Reload Configs**). Callers on shared addresses and hosting providers are the usual cases. See [[v4:connect:host_filter|Host Filter]].

===== SSH callers get a "host key changed" warning =====

The host key files in ''Configs'' were deleted or replaced. Keep them. Callers must accept the new key once. See [[v4:connect:ssh|SSH]].

===== FTP connects but cannot list or download =====

The control port is open but the data ports are not. Forward and allow the whole passive range (''50100-50200'' by default), and set **External address** to your public address or name. Behind a router "auto" is wrong. To check the settings, run ''PBFtp.exe -cfg Configs\PBFTP.CFG -test''. See [[v4:connect:ftp|FTP downloads]].

===== News (NNTP) will not connect =====

Run ''PBNntp.exe -cfg Configs\PBNNTP.CFG -test''. See [[v4:connect:nntp|News]].