My Book Live FTP?

WD Legacy Products My Book Live
9

… but the browser may try open more than one FTP connection to the the VSFTPD service.

I had the same problem. When I allowed two connections from the same IP the problem was was solved.  Try it.  You can but revert the setting to what it was if it does not work.

Remember to restart the VSFTPD service if you make any changes to vsftpd.conf