I have read though this forum, posts from people with similar issues. Checked all that was said there and still have a problem:
Set up client software on laptop, direct wired to system. Changed default port to 880 on system and in client software. Setup Dyndns to correct port and ip addy. Opened port 880 on Linksys WRT54GS router.
Dyndns reroute hasn't worked yet.
Remote viewing worked fine on 1st day wired directly to system, writed through router, over wireless and using air card. Opened the cameras with client app and through IE browser. Day 2, however, I get NOTHING. When I test using Dyndns Open Port 880 is not open. Tried changing it to other ports on system and in router, still nothing.
Called Comcast and they said only port sometimes blocked is 25. Read these forums and changed to TCP only, tried DMZ, nothing.