I used this when scripting using synchronize command for anonymous FTP:
Notice the 'anonymous' user name before the colon, nothing between the : and @ means the password is left blank. Without this the script halts. I think FTP should not halt, or a new option to open should be created to use anon instead of requiring authentication syntax for sites that don't require any authentication (public data).
Thanks for your post.
This issue is being tracked already: