Many thanks for taking the trouble to reply.
I have forwarded Port 5000 to the IP of the Server (inbound traffic) but still no joy.
(I only want to access files and manage the device remotely)
In the EZ-Interet settings of the Netgear it says
But, the 192.168.0.1 address is the router not the Synology.
So when I goto http://myname.dyndns.org
this is pointing to the router not the Synology server and I get the router logon screen instead of the Syniology.
If I goto 192.168.0.3 through my browser locally it calls up the synology fine.
Almost - but not quite working!