When you installed OBIEE that was with i guess different windows user and when you are restarting its with different user.
Make sure the user that is used to restart the service has admin provilleges and i suggest you to use same user to which you installed OBIEE.
We have tried using the same user who installed and now we are getting the below error
<Jul 10, 2014 2:31:24 PM IST> <Notice> <Log Management> <BEA-170019> <The server log file /dev/middlewareHome/user_projects/domains/bidev_domain/servers/AdminServer/logs/AdminServer.log is opened. All server side log events will be written to this file.>
<Jul 10, 2014 2:46:55 PM IST> <Notice> <WebLogicServer> <BEA-000388> <JVM called WLS shutdown hook. The server will force shutdown now>
<Jul 10, 2014 2:46:55 PM IST> <Alert> <WebLogicServer> <BEA-000396> <Server shutdown has been requested by <WLS Kernel>>
<Jul 10, 2014 2:46:55 PM IST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to FORCE_SHUTTING_DOWN>