Simple steps to ensure Pure-FTPd works on an EC2 instance:

1. Enable passive mode

sudo echo "50000 50100" > /etc/pure-ftpd/conf/PassivePortRange

2. Allow access to Public IP

sudo echo "public_ip" > /etc/pure-ftpd/conf/ForcePassiveIP

3. AWS Security Groups

Allow ports 50000 – 50100 to be open to anywhere

4. Restart Pure FTPd

sudo /etc/init.d/pure-ftpd restart

5. Test FTP access