I had the same problem. Now, my machine was set up initially on my wifi. Then, I moved to my home office and started using the wired connection. That never had a problem. Yesterday, for the first time, I tried working from my living room in the evening, and it would not connect. I saw one post somewhere that said your router has to be set up to let VPN pass through. Also, there was a discrepancy in the solutions on whether IPv6 should be enabled or not. I experimented with all combinations and it did not work. Finally, I tried to change the IPv6 setting on my router and it magically worked. For the record, I set the IPv6 value to "Auto Detect". I assume my router software chose this value. Now it works, and I'm not changing it! I have a Nighthawk MR60 distributed router (1+2 satellites) system. Hope it helps all the people struggling with this. My fix:
Good luck!