Ok here's the deal, I have a Mac OSX 10.4 Server that I just installed to host a couple of services that I need for my home. Basically, I need a server for FTP, Print Server, and VPN. So, I have all the services needed running and I'm ok with the print server. That's all good to go. Now my FTP I'm not too concerned about because I have tons of options for FTP. But my VPN is pretty critical and this is what I'm in desperate need of getting working. Now, internally I'm able to connect to the VPN server no problem. It's just when I get outside the network I'm not able to VPN. I have the VPN setup using L2TP over IPSec. I've gone on my router and forwarded ports 500 (UDP), 1701(UDP), 1723 (TCP) (even though this is for PPTP but just encase), 4500 (UDP) but I'm not able to connect. Then I tried putting my server in the DMZ and still wasn't able to connect. I have VPN passthrough set on my router also. My ISP is Comcast Infinity and I looked at their website to see what ports are being blocked on the ISP level. I've attached a list that shows the list of ISP level blocked ports.
From the list I don't see anything that should cause trouble except DHCP but I still wouldn't think that would be a problem, or could it be? If you think that could be a problem is there anything you can think of that I can bypass this? Any and all help would be all appreciated