Xlib: connection to ":3.0" refused by server Xlib: No protocol specified

This is a soluation for the problem  Xlib: connection to ":0.0" refused by server - X ;

 Hi, I can't run any program . getting this  Xlib: connection to ":0.0" refused by server Xlib: No protocol specified xeyes Xlib: connection to ":0.0" refused by server Xlib: No protocol

[oracle@hostname ~]$ dbca

Xlib: connection to ":3.0" refused by server 

   Xlib: No protocol specified

Need to login with the user not root....

[oracle10@db01 ~]$ vi ~/.vnc/xstartup

[oracle10@db01 ~]$ vncserver

You will require a password to access your desktops.

Password: type new password

Verify: retype

--(xauth:  creating new authority file /usr/oracle/.Xauthority

New 'db01.ct.com:3 (oracle10)' desktop is db01.ct.com:3 ,Creating default startup script /usr/oracle/.vnc/xstartup

Starting applications specified in /usr/oracle/.vnc/xstartup

Log file is /usr/oracle/.vnc/db01.ct.com:3.log)

[oracle10@db01 ~]$ vi ~/.vnc/xstartup

Uncomment  both the parameter  (# remove the hash sign  starting both of the line)

unset SESSION_MANAGER

 exec /etc/X11/xinit/xinitrc

 [oracle10@db01 ~]$ service vncserver start

-bash: service: command not found

[oracle10@db01 ~]$ vncserver

New 'db01.ct.com:4 (oracle10)' desktop is db01.ct.com:4

 Starting applications specified in /usr/oracle/.vnc/xstartup

 Log file is /usr/oracle/.vnc/db01.ct.com:4.log

[oracle10@db01 ~]$ dbca

now dbca will run successfully.......

All The Best........:)