I've had Verizon DSL using a Westell 6100 in bridge mode for ages without any problems at all. Recently I needed to change my Verizon Internet password and unfortunately for forgot to change it in my Netgear router behind the 6100. There must have been a brief disconnect of the DSL service and the router was unable to sign back in.
Even though I was receiving a DSL signal the router said that there was no Internet connection so I couldn't change my password. I reset the 6100 to stock (took it out of bridge), hooked up directly to the modem and was able to sign on to Verizon without the router and was able to browse.
Great, now I can just put the modem back into bridge mode and reconnect my router. Ummmmmm, not so fast. The modem would now not hold bridge mode. Whatever I did it would not get out of PPPoE. I know how to do it and have done several times. It would not work.
I called Verizon Tech Support and we walked through the same steps I'd already done. Nothing. They decided that I needed a new modem and are sending me one out.
Any ideas as to why the 6100 would not accept bridge mode just out of the blue. Makes no sense to me. Just curious.
Another option might be to leave the modem in PPPoE mode and configure the router appropriately which is the way I use my 6100 and router. My 6100 works in either PPoE or bridge mode, and I've no idea why yours no longer works in brider mode.