Invalid session error (no proxy)
I'm experiencing the same problem, yet I'm not using Apache or any other reverse proxy.
The forum is hosted on a remote VPS, and accessed directly from an IP address as it currently does not have a domain.
It didn't start right away, it worked normally in the beginning. Reloads and restarts don't help.
I have NodeBB 1.0.3 as well
Problem was solved by leaving blank the Cookie Domain field in Admin -> Settings -> Advanced