Yes,    that  issue was  created by  me.
We  have  fixed  the  problem.  We  have  removed  all  doubled files
like xwiki-platform-activeinstalls-common-8.1.jar *8.1.jar  in
/usr/lib/xwiki/WEB-INF/lib/  dir.
On 08.02.17 21:48, Vincent Massol wrote:
  Hi,
 I don’t know if it was you but this was also raised in jira at
 
https://jira.xwiki.org/browse/XE-1610
 I don’t know the answer as this stage but it looks very weird. I’m sure someone will
provide a solution by tomorrow EOD.
 Thanks
 -Vincent
> On 8 Feb 2017, at 18:42, Ligth <ya.est.svet(a)yandex.ru> wrote:
>
> Hi.
>
>
> We  have upgraded  xwiki  enterprise   from  8  to  9.0 versionb  on  debian:
>
> apt-get  update &&  apt-get  upgrade
>
> # dpkg -l | grep xwiki
> ii  xwiki-enterprise-common         9.0+3
> ii  xwiki-enterprise-pgsql-common   9.0+3
> ii  xwiki-enterprise-tomcat8-common 9.0+3
> ii  xwiki-enterprise-tomcat8-pgsql  9.0+3
>
>
> And  now  we  can't  get  started  xwiki.  The  following  error is  received:
>
> SEVERE: Exception sending context initialized event to listener instance of class
org.xwiki.container.servlet.XWikiServletContextListener
> java.lang.NoClassDefFoundError: Failed to get fields for class
[org.xwiki.activeinstalls.internal.client.DefaultPingSender] because the class
[io/searchbox/Action] couldn't be found in the ClassLoader.
>         at
org.xwiki.component.util.ReflectionUtils.getAllFields(ReflectionUtils.java:72)
>         at
org.xwiki.component.annotation.ComponentDescriptorFactory.createComponentDescriptor(ComponentDescriptorFactory.java:132)
>         at
org.xwiki.component.annotation.ComponentDescriptorFactory.createComponentDescriptors(ComponentDescriptorFactory.java:105)
>         at
org.xwiki.component.annotation.ComponentAnnotationLoader.register(ComponentAnnotationLoader.java:168)
>         at
org.xwiki.component.annotation.ComponentAnnotationLoader.initialize(ComponentAnnotationLoader.java:136)
>         at
org.xwiki.component.annotation.ComponentAnnotationLoader.initialize(ComponentAnnotationLoader.java:118)
>         at
org.xwiki.component.embed.EmbeddableComponentManager.initialize(EmbeddableComponentManager.java:151)
>         at
org.xwiki.container.servlet.XWikiServletContextListener.contextInitialized(XWikiServletContextListener.java:61)
>         at
org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4832)
>         at
org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5256)
>         at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
>         at
org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:724)
>         at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:700)
>         at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:714)
>         at
org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:581)
>         at
org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1685)
>         at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
>         at java.util.concurrent.FutureTask.run(FutureTask.java:266)
>         at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
>         at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
>         at java.lang.Thread.run(Thread.java:745)
>
> фев 08, 2017 6:03:35 PM org.apache.catalina.core.StandardContext startInternal
> SEVERE: Error listenerStart
>
>
> Can  someone   help ?
>
>
>