Migrating Servers Using SPFileZilla: Step-by-Step Tutorial

Troubleshooting SPFileZilla: Common Errors and Fixes

1. Connection refused / Unable to connect

• Cause: Server offline, wrong hostname/port, firewall, or incorrect protocol (SFTP vs FTP).
• Fixes:
  1. Verify host and port: Confirm server address and port (default FTP 21, SFTP 22).
  2. Check protocol: Switch between FTP/SFTP in SPFileZilla settings.
  3. Test server reachability: Ping the host or run telnet host port.
  4. Disable local firewall temporarily: If connection works, add SPFileZilla to allowed apps.
  5. Confirm server status: Contact the server admin or check server control panel.

2. Authentication failed / Incorrect credentials

• Cause: Wrong username/password, expired password, account lockout, or key mismatch.
• Fixes:
  1. Re-enter credentials carefully.
  2. Reset password via server control panel or admin.
  3. If using SSH keys: Ensure the private key is loaded in SPFileZilla and the public key is on the server with correct permissions (~/.ssh/authorized_keys).
  4. Check account restrictions: Confirm account permits the chosen protocol.

3. Permission denied when uploading or deleting files

• Cause: File/directory permissions or user lacks required privileges.
• Fixes:
  1. Check file permissions on server (ls -la) and adjust (chmod, chown) as appropriate.
  2. Use an account with correct privileges or ask the admin to grant write/delete access.
  3. Upload to a different directory you control, then move files server-side if possible.

4. Transfer stalled or very slow transfers

• Cause: Network issues, server load, MTU problems, or transfer mode mismatch (active vs passive).
• Fixes:
  1. Switch transfer mode: Try Passive if Active is selected, or vice versa (Site Manager → Transfer Settings).
  2. Limit simultaneous transfers: Reduce concurrent transfers in SPFileZilla settings.
  3. Test network speed and latency.
  4. Enable compression (if supported) or use binary mode for non-text files.
  5. Check for ISP or server-side throttling.

5. SSL/TLS errors or certificate warnings

• Cause: Self-signed certificate, expired certificate, or protocol mismatch.
• Fixes:
  1. Inspect certificate details when prompted and confirm the server fingerprint with the admin.
  2. Install a valid certificate on the server (Let’s Encrypt or other CA).
  3. Enable explicit FTPS or correct TLS settings in Site Manager.
  4. Avoid permanently accepting unknown certificates unless you verified the fingerprint.

6. Directory listing fails or shows incorrect files

• Cause: Passive/active FTP mismatch, wrong server root, charset differences.
• Fixes:
  1. Switch between active and passive FTP.
  2. Adjust character set in SPFileZilla if filenames appear garbled.
  3. Set correct server root or initial remote directory in Site Manager.
  4. Check server-side chroot or virtual user settings that restrict visible files.

7. “Connection timed out” errors

• Cause: Firewall, NAT/router blocking, wrong port, long server response time.
• Fixes:
  1. Increase timeout value in SPFileZilla settings.
  2. Open required ports on client and server firewalls and forward ports on routers if needed.
  3. Use passive mode to help with NAT traversal.

8. Hash/checksum mismatch after transfer

• Cause: Passive corruption, transfer mode wrong (ASCII vs binary), or disk issues.
• Fixes:
  1. Use binary mode for non-text files.
  2. Compare checksums (MD5/SHA) pre- and post-transfer; retransfer if mismatch.
  3. Inspect client/server disks for errors.

9. UI freezes or SPFileZilla crashes

• Cause: Large directory listings, corrupted settings, or memory limits.
• Fixes:
  1. Update to the latest SPFileZilla version.
  2. Clear cached settings or reset configuration.
  3. Avoid loading huge directories—navigate to subfolders or increase client memory if possible.
  4. Check system resource usage and close other heavy apps.

10. Unexpected permission prompts or ownership changes

• Cause: Server-side umask, FTP server configuration, or user mapping.
• Fixes:
  1. Adjust server umask or transfer umask settings.
  2. Use SFTP which preserves permissions more consistently.
  3. Coordinate with server admin to set correct default ownership for uploaded files.

Quick troubleshooting checklist

1. Confirm host, port, and protocol.
2. Double-check credentials and keys.
3. Switch active/passive and ASCII/binary modes.
4. Test connectivity (ping/telnet) and check firewalls.
5. Reduce simultaneous transfers and update SPFileZilla.

If you want, I can convert this into a printable one-page cheat sheet or produce step-by-step commands for a specific OS/server — tell me which OS/server to target.