How can I troubleshoot the 'Remote side unexpectedly closed network connection' error?

This error typically occurs when the SFTP/FTP server closes the connection before communication can fully establish. Based on real cases, common causes include:

• The server was temporarily offline or undergoing maintenance.

• Your connection attempt is blocked because the server has not whitelisted your IP address.

• The server requires a specific port (commonly port 22 for SFTP) and the network does not allow outbound traffic on that port.

• The server accepts connection attempts from tools like FileZilla or WinSCP, but automated connections (such as from Stock Sync) may still be blocked until the server whitelists the correct IP.

If you receive this error, confirm with the source provider:

• Whether their server is online and accessible.

• That your IP address is fully whitelisted.

• That the correct port is open.

• Whether they can connect from their side and provide a screenshot for verification.

Once the server confirms correct configuration, try reconnecting from Stock Sync again.

Updated on: 09/06/2026