Xlib: connection to "x:0.0" refused by server

Problem:

When you running concurrent reports you get this error.

Xlib: connection to "x:0.0" refused by server

Xlib: Invalid MIT-MAGIC-COOKIE-1 key

REP-3000: Internal error starting Oracle Toolkit

REP-0004: Warning: Unable to open user preference file while running reports.

xlib connection to 1.0 refused by server oracle concurrent

Xlib: connection to "hostname:1.0" refused by server

Solution:

su - root

export DISPLAY=hostname:1.0

xhost +

./adcmtl.sh stop

./adcmtl.sh start

Note:
This problem happened AIX,SOLARIS OS,not LINUX.Because  reports use DISPLAY,Linux OS has DISPLAY,but others doesn't have.If you use Linux,don't panic.You won't come across this problem:)