FTP transfer stalls
Why FTP transfers stall mid-transfer and how to troubleshoot data channel issues.
Diagnose this automatically
Test whether the server allows directory listing with valid credentials.
Shareable output
Prefer the browser? Run the same check on the homepage.
FTP transfers may stall when the data channel is interrupted.
Common causes
- Passive ports blocked
- Network congestion
- Firewall inspection interfering
Fix checklist
- Verify passive port configuration.
- Check firewall data channel rules.
- Test transfer from another network.
FTPMonitor Help
Still stuck? We can help diagnose and fix it.
Choose the level of help that matches the urgency. Never send passwords, private keys, or other secrets.
Fix Report
$49
A written diagnosis and recommended fix for one FTP, FTPS, or SFTP issue.
- Written diagnosis
- Recommended fix steps
- Best for non-urgent issues
Recommended
Same-Day Help
$149
Priority troubleshooting for one active issue, with a clear same-day diagnosis and action plan.
- Priority troubleshooting
- Same-day diagnosis and action plan
- Best for active business problems
Live Fix Call
$299
Live troubleshooting help for an urgent or unusually complex FTP, FTPS, or SFTP problem.
- Live troubleshooting session
- Best for urgent or complex failures
- Scheduling coordinated after checkout
Related
- FTP passive mode firewall issues — Why FTP PASV fails behind firewalls/NAT and how to configure passive ports correctly.
- FTP data connection failed — Why FTP data connections fail and how to troubleshoot passive and active data channel issues.
- FTP directory listing timeout — Why FTP directory listings hang or timeout and how to resolve passive mode firewall problems.
- FTP passive mode not working — Why FTP passive mode fails and how to configure passive ports and NAT correctly.
- FTP EPSV error — Understanding FTP EPSV errors and how to resolve extended passive mode problems.
- FTP timeout during transfer — Why FTP transfers timeout and how to fix idle timeout or firewall issues.
Diagnostics powered by FTPMonitor CLI