Problem with the installaion of pentaho:Pentaho Initialization Exception

Hello,
I have tried several versions of Pentaho BI, the community edition(the 5.3.0.0-213, and the 6.0.1.0.386), with both jdk 7 u79, jdk8u20,but i still have the same error and i'm already fed up of trying to fix it.
I got this error when i launched it:

Please see the server console for more details on each error detected.

Here is my pentaho.log
2016-02-24 18:16:49,862 ERROR [org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener]
org.pentaho.platform.api.engine.security.userroledao.AlreadyExistsException:
at org.pentaho.platform.security.userroledao.jackrabbit.JcrUserRoleDao.createRole(JcrUserRoleDao.java:123)
at org.pentaho.platform.repository2.mt.RepositoryTenantManager.createTenant(RepositoryTenantManager.java:202)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy28.createTenant(Unknown Source)
at org.pentaho.platform.repository2.unified.lifecycle.DefaultBackingRepositoryLifecycleManager.startup(DefaultBackingRepositoryLifecycleManager.java:164)
at org.pentaho.platform.repository2.unified.lifecycle.DelegatingBackingRepositoryLifecycleManager.startup(DelegatingBackingRepositoryLifecycleManager.java:87)
at org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener.startup(BackingRepositoryLifecycleManagerSystemListener.java:59)
at org.pentaho.platform.engine.core.system.PentahoSystem$2.call(PentahoSystem.java:421)
at org.pentaho.platform.engine.core.system.PentahoSystem$2.call(PentahoSystem.java:412)
at org.pentaho.platform.engine.core.system.PentahoSystem.runAsSystem(PentahoSystem.java:391)
at org.pentaho.platform.engine.core.system.PentahoSystem.notifySystemListenersOfStartup(PentahoSystem.java:412)
at org.pentaho.platform.engine.core.system.PentahoSystem.access$000(PentahoSystem.java:77)
at org.pentaho.platform.engine.core.system.PentahoSystem$1.call(PentahoSystem.java:343)
at org.pentaho.platform.engine.core.system.PentahoSystem$1.call(PentahoSystem.java:340)
at org.pentaho.platform.engine.core.system.PentahoSystem.runAsSystem(PentahoSystem.java:391)
at org.pentaho.platform.engine.core.system.PentahoSystem.notifySystemListenersOfStartup(PentahoSystem.java:340)
at org.pentaho.platform.engine.core.system.PentahoSystem.init(PentahoSystem.java:311)
at org.pentaho.platform.engine.core.system.PentahoSystem.init(PentahoSystem.java:212)
at org.pentaho.platform.web.http.context.SolutionContextListener.contextInitialized(SolutionContextListener.java:135)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4210)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4709)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:583)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:675)
at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:601)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:502)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1317)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1065)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:822)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
2016-02-24 18:16:52,385 ERROR [org.pentaho.platform.util.logging.Logger] Error: Pentaho
2016-02-24 18:16:52,385 ERROR [org.pentaho.platform.util.logging.Logger] misc-org.pentaho.platform.engine.core.system.PentahoSystem: org.pentaho.platform.api.engine.PentahoSystemException: PentahoSystem.ERROR_0014 - [fr_71] Error while trying to execute startup sequence for org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener
org.pentaho.platform.api.engine.PentahoSystemException: org.pentaho.platform.api.engine.PentahoSystemException: PentahoSystem.ERROR_0014 - [fr_71] Error while trying to execute startup sequence for org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener
at org.pentaho.platform.engine.core.system.PentahoSystem.notifySystemListenersOfStartup(PentahoSystem.java:348)
at org.pentaho.platform.engine.core.system.PentahoSystem.init(PentahoSystem.java:311)
at org.pentaho.platform.engine.core.system.PentahoSystem.init(PentahoSystem.java:212)
at org.pentaho.platform.web.http.context.SolutionContextListener.contextInitialized(SolutionContextListener.java:135)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4210)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4709)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:583)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:675)
at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:601)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:502)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1317)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1065)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:822)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: org.pentaho.platform.api.engine.PentahoSystemException: PentahoSystem.ERROR_0014 - [fr_71] Error while trying to execute startup sequence for org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener
at org.pentaho.platform.engine.core.system.PentahoSystem$2.call(PentahoSystem.java:430)
at org.pentaho.platform.engine.core.system.PentahoSystem$2.call(PentahoSystem.java:412)
at org.pentaho.platform.engine.core.system.PentahoSystem.runAsSystem(PentahoSystem.java:391)
at org.pentaho.platform.engine.core.system.PentahoSystem.notifySystemListenersOfStartup(PentahoSystem.java:412)
at org.pentaho.platform.engine.core.system.PentahoSystem.access$000(PentahoSystem.java:77)
at org.pentaho.platform.engine.core.system.PentahoSystem$1.call(PentahoSystem.java:343)
at org.pentaho.platform.engine.core.system.PentahoSystem$1.call(PentahoSystem.java:340)
at org.pentaho.platform.engine.core.system.PentahoSystem.runAsSystem(PentahoSystem.java:391)
at org.pentaho.platform.engine.core.system.PentahoSystem.notifySystemListenersOfStartup(PentahoSystem.java:340)
... 27 more
Caused by: org.pentaho.platform.api.engine.PentahoSystemException: PentahoSystem.ERROR_0014 - [fr_71] Error while trying to execute startup sequence for org.pentaho.platform.repository2.unified.BackingRepositoryLifecycleManagerSystemListener
at org.pentaho.platform.engine.core.system.PentahoSystem$2.call(PentahoSystem.java:422)
... 35 more
2016-02-24 18:16:52,385 ERROR [org.pentaho.platform.util.logging.Logger] Error end:


Please i will be very grateful if someone could help to fix it!!