Just like FileZilla, SmartFTP can open too many simultaneous connections to the server, causing timeouts and "421 Too many connections" errors. Here is how to limit concurrent connections in SmartFTP.
Limit connections to 2 in SmartFTP
Go to Tools > Settings > Transfer > General and set "Max Connections" to 2. This prevents the server from rejecting your connections due to per-IP limits.
01. How to Change the Setting
- Open SmartFTP
- Go to Tools > Settings
- Navigate to Transfer > General
- Set "Max Connections" to 2
- Click OK
You can also set this per-connection in the Favorites/connection properties if you want different limits for different servers.
02. Other Recommended Settings
- Transfer mode: Passive (under Connection > FTP > Data Connection)
- Encryption: Explicit TLS (under Connection > Security)
- Timeout: Increase to 60 seconds if you experience disconnects
These are the same best practices as for any FTP client on our servers. For detailed guidance on FTP setup with other clients, see our FTP client guide. For FileZilla-specific settings, see Changing Concurrent Connections in FileZilla.
FTP Connection Issues?
If adjusting connection limits does not help, open a ticket with details about the error you see.
Open a Support TicketQuick Recap
- Set Max Connections to 2 in Tools > Settings > Transfer > General
- Use passive mode for reliable connections
- Enable explicit TLS for encrypted transfers
- Increase timeout if connections drop frequently
- Same principles apply to FileZilla, WinSCP, and other clients
FTP client configuration · Last updated March 2026 · Browse all FTP articles
