Verizon is requesting all of its users to change the server settings or come Sept 2013, problems will abound if no compliance. I have tried to do this with no luck. I receive an error msg after change. I use Thunderbird email - Win7 - Chrome. A certificate warning from Avast pops up that warns me away from the change due to lack of compliant certificate. Is Avast blocking this action?? Any thoughts - thanks very much.