Case: SmartDashboard could not be opened, giving the Connection and GUI Client Error. When the migrate export file used in sandbox, the problem did not persist. To resolve the issue; the CMI Temp files deleted and forced to be re-created on startup.
2. cd $FWDIR/conf
mv applications.C applications.C.old
mv applications.C.backup applications.C.backup.old
mv CPMILinksMgr.db CPMILinksMgr.db.old
mv CPMILinksMgr.db.private CPMILinksMgr.db.private.old