Unable to start the Weblogic AdminServer 12c: Server subsystem failed. Reason: java.lang.NullPointerException

Scenario:

Users were unable to start the AdminServer ( weblogic 12c). The startup failed with following error

####<Jul 31, 2013 4:47:04 AM PDT> <Critical> <WebLogicServer> <host02> <AdminServer> <main> <<WLS Kernel>> <> <> <1375271224766> <BEA-000386> <Server subsystem failed. Reason: java.lang.NullPointerException 
java.lang.NullPointerException at weblogic.management.internal.PendingDirectoryManager.find(PendingDirectoryManager.java:571) at weblogic.management.internal.PendingDirectoryManager.find(PendingDirectoryManager.java:556) at weblogic.management.internal.PendingDirectoryManager.find(PendingDirectoryManager.java:575)  at weblogic.management.internal.PendingDirectoryManager.find(PendingDirectoryManager.java:556) at weblogic.management.internal.PendingDirectoryManager.getAllFiles(PendingDirectoryManager.java:413) at weblogic.management.provider.internal.EditAccessImpl.<init>(EditAccessImpl.java:165)

Reason:

One user stopped and restarted the Admin service as "root" user instead of the S/W owner (which was oracle). He also tried to create datasources for the application after starting up the weblogic Admin server.

Impact:

The action modified the ownership and permissions on many of the domain's folders to root. This was stopping the Admin server from coming up.

Tried few work around like renaming the AdminServer folder and then starting up, removing the replicas.prop file under AdminServer/data/ldap/conf directory and renaming WLS_DIAGNOSTICS000000.DAT file under AdminServer/data/store/diagnostics location. But nothing worked in this case.

Solution:

Check for the permission of "pending" folder under $DOMAIN_HOME. If it is under root move it back to oracle (or the original WLS S/W owner).

Also check whether we have any files under pending. If so we can rename them too

chown -R oracle:oinstall pending

This did the trick. After this I was able to start up the AdminServer.