Ok, I'm pissed of ... this is the second D-Link router that is giving me crap and I'm about to give up on the brand completely.
Obviously I have the DGL-4500 and I have some Virtual Servers setup for forwarding HTTP/SSH and they work fine, but my computer's local IP changed so I wanted to update the IP in the list.  Everytime I tried to make the update and save it I would loose connection because the router reboots.  When I go back in and just try to disable any current virtual server it reboots after you press the OK.
What the helL!?!?
So, next I try to update the firmware from 1.15 to 1.22.  I upload the new firmware and it says success but when it reboots the firmware is still 1.15.  So I try again.  I try 1.21.  I try downgrading 1.13 and NOTHING.  It won't budge.  No errors, no warnings, no nothing. 
What the heck can I do, short of buying a different brand router!?