I just installed the tightvncserver on an Ubuntu Mate, and now I am locked out of my VM…I am stuck at the login page, type my credentials and it lands back again at the login page, I can also tell the resolution of the entire VM was adjusted to the res of the vnc server…Please help!
try pressing Ctrl + Alt + F1 when at the display manager login screen. This will change from the default tty7 to tty1.
If there are any errors you will see them and that should get you going in the right direction.