I can run vncserver manually but when I reboot it does not automatically start. It was working in the past but just stopped. Here's some of the things I've checked:

1. I've used update-rc.d to remove and readd its config (sudo update-rc.d vncserver defaults)
2. I've checked /etc/init.d/vncserver is executable
3. I've checked ~/.vnc/xstartup is executable
4. When I run vncserver start manually there are no errors and it starts properly...but after a reboot it never starts.

What can I do to troubleshoot this? I cannot find any logs anywhere. I have many other services that auto-start properly.