USB Sharing type FTP (via internet) suddenly stopped working

Hi,

I have been sucessfully using the FTP via internet setting until one day it just stopped working.

After extensive debugging I simply cannot explain it!

The URL is ... ftp://myrs.mynetgear.com:1921/shares/

It just won't connect, times out on connection, nothing has changed.  All the other sharing options work, including FTP from inside the network!

I have tried it with the direct IP and with port 21, and every security setting there is and I still get nothing.

Please help as the only option I have left is a warranty claim which seems silly given it's a software problem!