This error is peculiar to WS_FTP, and generally indicates a problem with a router (sometimes referred to as a "blackhole router") between your computer and the Network Solutions network.

In your WS_FTP configuration, change the setting for Passive Transfers.

n If the Passive Transfers is enabled, then disable it

n If the Passive Transfers is disabled, then enable it

You can typically find the Passive Transfer setting under Session Properties and the Advanced tab.