Xlib: connection to ":1.0" refused by server Xlib: No protocol specified

xhost +

Sounds like you are trying to access X as a non-authorised user.
The only time I ever see those lines is when I have done "su" in a shell and then attempt to run a program.
If this is the problem, then make sure you are the correct user (i.e. the one you originally did startx with or logged in on a graphical login manager with)
If not, then try "xhost +" first.

from http://www.linuxquestions.org/questions/linux-newbie-8/xlib-connection-to-0.0-refused-by-server-xlib-no-protocol-specified-152556/?s=a1dfa399434016c0a156c6d22278d572