Problem with remote administration?

[Severus]

I have a problem with UVNC remote administration. My IP is static, I checked. Also, I have secured a domain and DNS and installed DNS updater to be handy whenever I use DHCP. My helpdeck.txt is OK, this has been checked too. All listening ports that might be needed are open. Nevertheless, I can't get any UVNC (SC, PChelpware, TIghtVNC, etc.) to work. Also, I've been able to self-loop (the same machine acting as VNC server and viewer) with all these products, but I can't make a connection with the target computers.
Any suggestions where I might have done something not right? Thanks for any help.

[apeskape]

If you or the target computer are behind a router you will need to be inside of the DMZ zone of it.

http://www.geocities.com/jimbobjoe14580/dmz.html