Unable to access POP3 e-mail without VPN

            I have used Thunderbird to access my e-mail from Cox via POP3 for years. Thursday afternoon (December 10), I started experiencing the inability to access my e-mail via POP3 (using Thunderbird), receiving the message "Sending of password for user ***** did not succeed. Mail server pop.cox.net responded: invalid user name or password" even though the username and password were correct. I have experienced that continuously through now (Saturday noon, December 12). I have made no changes in software, and no changes in settings within Thunderbird. I have been able to access e-mail via the Web mail interface (using the same username and password) throughout this time. I have called Cox technical support four times over the past two days. Each time I was told that Cox was experiencing significant problems with their e-mail servers, sometimes including Web mail outages. The service personnel said they had been receiving many, many phone calls about this.

            This morning when I called, I was told the same thing. I then asked to be connected to Tier 2 support. The person who answered (after 15 minutes on hold) told me that there was no problem with any of the Cox e-mail servers, Web or POP3; that there had been no problems over the past few days; and that nothing had changed in their configuration. He said that what I had been told by the other technical support personnel was incorrect! He checked my settings in Thunderbird, said they were correct, and said that Cox didn't support Thunderbird. He then said that since I could log into Web mail, there obviously was no problem with Cox e-mail, and the problem therefore had to be with my software. He offered me no help, other than to try some other third-party software. He refused to consider the possibility that Cox’s POP3 configuration might have changed without affecting the Web mail accessibility.

         I subsequently called back to technical support, and had them reset my password, just to see if that was the problem. That had no effect.

         I finally tried using Thunderbird with a VPN. Everything worked normally! Whatever changed on Cox’s end was masked by the VPN. If someone can explain all of this, I would be grateful. I would be even more grateful if someone can get Cox’s configuration changed back so that POP3 e-mail works as it had before, without requiring a VPN to access it.