Rebooting the router caused this problem on my side. I finally got the thing stable where I could access my dvr's from the web. It lasted about two weeks when there was a power failure and my router was rebooted. Now I have tried everything and all I get is bad gateway.
Also, if you go into the STB, hit menu and choose customer support then run self diagnostics.
From here you can see if the STB can communicate properly with the Verizon Servers. Please report back results of this screen.
I just tried this and I received another error message ---- "unable to retrieve DVR information". I'm thinking that this may be a router issue as this problem seemed to start around the time I needed to reset the router.
I had this problem, and Verizon couldn't figure it out. It started working after I installed a couple of Fios apps on my iPhone. One was the Fios DVR Manager, and the other was the Fios Mobile Remote.