[INS-08101] Unexpected error while executing the action at state: 'performChecks

When you install or upgrade from 11gR1 to 12c you can see below error in installer log file(  /tmp/OraInstall2014-12-08_11-32-53AM.) or installer stop to move next step.

ID: oracle.install.commons.util.exception.DefaultErrorAdvisor:608
oracle.install.commons.flow.FlowException: [INS-08101] Unexpected error while executing the action at state: 'performChecks'
        at oracle.install.commons.flow.AbstractFlowExecutor.startAction(AbstractFlowExecutor.java:368)
        at oracle.install.commons.flow.AbstractFlowExecutor.enterVertex(AbstractFlowExecutor.java:601)
        at oracle.install.commons.flow.AbstractFlowExecutor.transition(AbstractFlowExecutor.java:341)
        at oracle.install.commons.flow.AbstractFlowExecutor.nextState(AbstractFlowExecutor.java:276)
        at oracle.install.commons.flow.AbstractFlowExecutor.nextViewState(AbstractFlowExecutor.java:235)
        at oracle.install.commons.flow.DefaultFlowNavigator.goForward(DefaultFlowNavigator.java:58)
        at oracle.install.commons.flow.jewt.FlowWizard$1.run(FlowWizard.java:137)
        at oracle.install.commons.flow.jewt.FlowWizard$TransitionManager$1.run(FlowWizard.java:113)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
        at java.lang.Thread.run(Thread.java:682)
Caused by: java.lang.NullPointerException
        at oracle.ops.mgmt.cluster.ClusterInfo.getReleaseVersionString(ClusterInfo.java:1991)
        at oracle.ops.mgmt.cluster.ClusterInfo.getSIHAReleaseVersionString(ClusterInfo.java:1431)
        at oracle.ops.verification.framework.util.VerificationUtil.getSIHAReleaseVersionObjWithException(VerificationUtil.java:7946)
        at oracle.ops.verification.framework.util.VerificationUtil.getSIHAReleaseVersionObjWithException(VerificationUtil.java:7919)
        at oracle.ops.verification.framework.util.VerificationUtil.getSIHAReleaseVersionObj(VerificationUtil.java:7851)
        at oracle.ops.verification.framework.util.VerificationUtil.getSIHAReleaseVersionObj(VerificationUtil.java:7791)
        at oracle.ops.verification.framework.engine.task.TaskFactory.isLocalNodeCRSRunning(TaskFactory.java:1457)
        at oracle.ops.verification.framework.engine.task.TaskFactory.getTaskListSysReq(TaskFactory.java:4738)
        at oracle.ops.verification.framework.engine.task.TaskFactory.getTaskListSysReq(TaskFactory.java:4440)
        at oracle.ops.verification.framework.engine.task.TaskFactory.getTaskListPreSIDBInst(TaskFactory.java:2763)
        at oracle.ops.verification.framework.engine.task.TaskFactory.getTaskList(TaskFactory.java:581)
        at oracle.ops.verification.framework.engine.task.TaskFactory.getTaskList(TaskFactory.java:830)
        at oracle.cluster.verification.ClusterVerification.getPreReqTasksForSIDBInst(ClusterVerification.java:1012)
        at oracle.install.library.util.cvu.CVUHelper.getPreReqTasksForSIDBInst(CVUHelper.java:414)
        at oracle.install.ivw.db.action.PrereqAction.getProductVerificationTasks(PrereqAction.java:131)
        at oracle.install.commons.base.interview.common.action.AbstractPrereqAction.execute(AbstractPrereqAction.java:89)
        at oracle.install.commons.flow.AbstractFlowExecutor.startAction(AbstractFlowExecutor.java:366)
        ... 13 more

---# End Stacktrace #-----------------------------

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Problem:

ORA_NLS10 setting is incorrect. 

Fix:

For 11g/12c, it's unnecessary to set ORA_NLS10. The issue was solved after the environment variable is unset and installer restarted.