Unable to Connect to FTP Server hosted on my PC from another device

I set up FileZilla Server on my Windows 10, allowed it through the firewall. I can access it on browser and file explorer on the same machine. But I'm unable to access it on my phone which is on the same local network. On my Connection Wizard, these are the configurations:

Connection type: FTP
Remote hostname: 192.168.137.1
Port number: 21
Authentication: Username and password
Username: ftpuser

I'm using Solid File Explorer on my android, and I receive the following error: A problem occurred with network communication. Nothing happens on the FileZilla log. What could be the problem?

What could be the problem?

Solid File Explorer defaults to Passive mode FTP (under "Set advanced?" -> "Yes" -> "Connection mode" in the Connection Wizard), which requires at least two ports to work:

1. A control port (e.g. port 21)
2. At least one data transfer port (e.g. port 20 or some other port range)

Based on some light testing, it seems likely one (or more) of these ports are being blocked, preventing Solid File Explorer from establishing a connection.

Troubleshooting

I might suggest looking at your Windows Firewall settings again, as well as any anti-virus program you may have that might include some kind of Wifi protection. You can try (temporarily) disabling these services entirely before attempting to establish an FTP connection to see if that makes a difference.

Skipping Windows 10 Settings, you can disable the Windows Firewall completely for both Private and Public networks under Control Panel\System and Security\Windows Defender Firewall.

Technically, for FileZilla Server.exe and Passive mode, you should only need a single Inbound rule (looking at the Advanced settings for Windows Firewall). But it might be worthwhile to try applying it to both Private and Public networks if it isn't already.

If your Windows Firewall rules are for port ranges, they should likely be for ports 20 and 21 by default. Otherwise, they should be for the ports you are actually using for control and data transfer (set under FileZilla Server with Options -> General settings and Options -> Passive Mode settings).

Other Possibilities

• Theoretically, you may need to forward these same ports in your router to the correct host running FileZilla. Typically this is only necessary for accessing FileZilla from outside your local network, but...? If you do this, you should probably take a look at this general guide to hardening FileZilla Server.

• FileZilla may be set to only accept connections from certain IPs. You can can look at this information under FileZilla Server's Options -> General Settings -> IP bindings and Options -> General settings -> IP filter. IP bindings defaults to * and IP filter defaults to empty fields (which should both allow general connections)