Server & Hosting Mr. Boyd

FTP Connections

Fix authentication errors, configure your FTP client, and understand the differences between FTP, SFTP, and FTPS.

What Is FTP?

File Transfer Protocol (FTP) is a standard network protocol used to transfer files between a client and a server. It typically operates on port 21 for the control channel and uses additional ports for data transfer.

Personally, I prefer the client FileZilla for uploading files via FTP, however it is understandable if you use your own personal client.

FTP vs SFTP vs FTPS

Security Comparison

FTP — Unencrypted. Credentials sent in plain text. Avoid if possible.
FTPS — FTP over SSL/TLS. Encrypted but can have firewall issues with passive mode.
SFTP — SSH File Transfer Protocol. Runs over SSH (port 22). Most secure option. See SSH Essentials.

The 530 Authentication Error

When attempting to FTP you may come across errors such as 530 Authentication Error. This error indicates an issue with the credentials being entered for the FTP user.

Common Causes

  • Wrong username format — secondary FTP users on cPanel require: username@primarydomain.tld
  • Incorrect password — reset the FTP password in cPanel → FTP Accounts
  • IP blocked — too many failed login attempts triggered a firewall block (check cSF/fail2ban)
  • Account suspended or disabled — check with your hosting provider
cPanel FTP Username Format

If you are using a secondary FTP user on cPanel, the format for the username should be: username@primarydomain.tld. The main cPanel username does not require this format.

FileZilla Connection Setup

Open Site Manager

In FileZilla, go to File → Site Manager (or press Ctrl+S).

Enter Connection Details

Host:     yourdomain.com (or server IP)
Port:     21 (FTP) or 22 (SFTP)
Protocol: FTP or SFTP
Logon Type: Normal
User:     your_ftp_username
Password: your_ftp_password

Set Transfer Mode

Go to the Transfer Settings tab and select Passive mode. This is required for most firewalled hosting environments.

Connect

Click Connect. If you get a certificate warning for FTPS/SFTP, verify the fingerprint matches your server and accept it.

Passive vs Active Mode

Active mode: The server initiates the data connection back to the client. Often blocked by client-side firewalls and NAT routers.

Passive mode: The client initiates both the control and data connections. Works through most firewalls. Use passive mode by default.

Connection Timeout Issues

  • Verify the hostname/IP is correct and the server is online
  • Check that port 21 (or 22 for SFTP) is open on the server firewall
  • Try connecting from a different network to rule out local firewall blocks
  • Increase the timeout setting in your FTP client (FileZilla: Edit → Settings → Connection → Timeout)

File Permissions After Upload

After uploading files, ensure proper permissions are set:

# Standard permissions
Files:       644 (rw-r--r--)
Directories: 755 (rwxr-xr-x)

# In FileZilla: right-click file → File Permissions
# Or via SSH:
chmod 644 filename.php
chmod 755 directory_name/
Pro Tip

Consider switching to SFTP instead of plain FTP. It uses SSH encryption, runs on port 22, and most modern hosting accounts support it. See our SSH Essentials guide for setup details.