Blank screen after first admin login to Webtop5

NethServer Version: NethServer release 7.3.1611 (Final)
Module: Webtop5

I have a fresh installation of nethserver. I added a webtop 5 with no errors. After login with admin/admin, only blank page (nothing on it) opened. In a log I see couple errors, but have absolutely no idea what I can do about it.
There is today’s log for webtop:

2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - webtop.extjsdebug = true
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - webtop.soextdevmode = false
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - webtop.devmode = true
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - webtop.debugmode = false
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - webtop.scheduler.disabled = false
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - WTA initialization started [webtop]
2017-05-05 07:31:06 [INFO ] c.s.w.core.app.ConnectionManager - ConnectionManager initialized
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.SettingsManager - SettingsManager initialized
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.SessionManager - SessionManager initialized
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Checking home structure…
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.I18nManager - I18nManager initialized.
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Initializing template engine
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.LogManager - LogManager initialized.
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.WebTopManager - WebTopManager initialized
2017-05-05 07:31:06 [INFO ] c.sonicle.webtop.core.app.OTPManager - OTPManager initialized
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.ReportManager - ReportManager initialized.
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.core]
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:true, job:true, userOptions:true]
2017-05-05 07:31:06 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Database upgrades will be appended to 1493994667056
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.core.admin]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:false, job:false, userOptions:false]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.calendar]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:true, job:false, userOptions:true]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.contacts]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:false, job:false, userOptions:true]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.mail]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:false, job:true, userOptions:true]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.tasks]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:false, job:false, userOptions:true]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Registering service [com.sonicle.webtop.vfs]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - [private:true, public:true, job:false, userOptions:true]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - Not upgraded! [5.0.0 = 5.0.0]
2017-05-05 07:31:07 [INFO ] c.s.webtop.core.app.ServiceManager - ServiceManager initialized
2017-05-05 07:31:07 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Admin session created [331a9229-7d78-42da-a4a1-2266ddea9d82]
2017-05-05 07:31:07 [INFO ] c.sonicle.webtop.core.app.WebTopApp - adminTouch task scheduled [1620sec]
2017-05-05 07:31:07 [INFO ] c.sonicle.webtop.core.app.WebTopApp - WTA initialization completed [webtop]
2017-05-05 07:31:12 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Checking domains homes structure…
2017-05-05 07:31:12 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Checking webapp version…
2017-05-05 07:31:12 [WARN ] c.sonicle.webtop.core.app.WebTopApp - No configuration found for TomcatManager [tomcat.manager.uri]
2017-05-05 07:31:12 [WARN ] c.sonicle.webtop.core.app.WebTopApp - Webapp version automatic check will NOT be performed!
2017-05-05 07:31:12 [INFO ] c.sonicle.webtop.core.app.WebTopApp - This webapp [webtop] is the latest
2017-05-05 07:31:12 [INFO ] c.sonicle.webtop.core.app.WebTopApp - Scheduling JobServices tasks…
2017-05-05 10:11:39 [ERROR] c.s.webtop.core.app.ServiceManager - PrivateService: initialize() throws errors [com.sonicle.webtop.core.admin.Service] java.lang.ClassCastException: com.sonicle.webtop.core.CoreManager cannot be cast to com.sonicle.webtop.core.admin.CoreAdminManager
at com.sonicle.webtop.core.admin.Service.initialize(Service.java:117)
at com.sonicle.webtop.core.app.ServiceManager.instantiatePrivateService(ServiceManager.java:779)
at com.sonicle.webtop.core.app.WebTopSession.internalInitPrivateEnvironment(WebTopSession.java:402)
at com.sonicle.webtop.core.app.WebTopSession.initPrivateEnvironment(WebTopSession.java:320)
at com.sonicle.webtop.core.servlet.Start.processRequest(Start.java:88)
at com.sonicle.webtop.core.app.AbstractServlet.doGet(AbstractServlet.java:76)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)
at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:683)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
2017-05-05 10:11:39 [ERROR] c.sonicle.webtop.core.servlet.Start - Error com.sonicle.webtop.core.sdk.WTRuntimeException: Cannot add private service twice
at com.sonicle.webtop.core.app.WebTopSession.cachePrivateService(WebTopSession.java:565)
at com.sonicle.webtop.core.app.WebTopSession.internalInitPrivateEnvironment(WebTopSession.java:405)
at com.sonicle.webtop.core.app.WebTopSession.initPrivateEnvironment(WebTopSession.java:320)
at com.sonicle.webtop.core.servlet.Start.processRequest(Start.java:88)
at com.sonicle.webtop.core.app.AbstractServlet.doGet(AbstractServlet.java:76)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)
at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:683)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)

Is there some pre-installation requirement for webtop5? I assumed (as far as package is included in server approved software), that it will install all necessary dependencies. And this is not my first unsuccessful installation of webtop5. First I tried to install it on server, which has been updated (several times) from alpha. This time I made a clean installation from final release with no errors during installation (unfortunately also unsuccessful). What am I doing wrong?

No one?
Can somebody at least put repeatable working sequence of installation server and webtop 5 here? It should be something simple, which I am missing.

Tried a clean install yesterday an was unable to reproduce the problem.

cc/ @webtop_team, don’t know what’s causing this error on your setup:

I have the same thing when installing webtop5.
I can log in with a domain user but the admin / admin user displays a blank window.

2017-05-27 21:18:23 [ERROR] c.s.webtop.core.app.ServiceManager - PrivateService: initialize() throws errors [com.sonicle.webtop.core.admin.Service]
java.lang.ClassCastException: com.sonicle.webtop.core.CoreManager cannot be cast to com.sonicle.webtop.core.admin.CoreAdminManager
at com.sonicle.webtop.core.admin.Service.initialize(Service.java:117)
at com.sonicle.webtop.core.app.ServiceManager.instantiatePrivateService(ServiceManager.java:779)
at com.sonicle.webtop.core.app.WebTopSession.internalInitPrivateEnvironment(WebTopSession.java:402)
at com.sonicle.webtop.core.app.WebTopSession.initPrivateEnvironment(WebTopSession.java:320)
at com.sonicle.webtop.core.servlet.Start.processRequest(Start.java:89)
at com.sonicle.webtop.core.app.AbstractServlet.doGet(AbstractServlet.java:71)
2017-05-27 21:18:23 [ERROR] c.sonicle.webtop.core.servlet.Start - Error
com.sonicle.webtop.core.sdk.WTRuntimeException: Cannot add private service twice
at com.sonicle.webtop.core.app.WebTopSession.cachePrivateService(WebTopSession.java:565)
at com.sonicle.webtop.core.app.WebTopSession.internalInitPrivateEnvironment(WebTopSession.java:405)
at com.sonicle.webtop.core.app.WebTopSession.initPrivateEnvironment(WebTopSession.java:320)
at com.sonicle.webtop.core.servlet.Start.processRequest(Start.java:89)
at com.sonicle.webtop.core.app.AbstractServlet.doGet(AbstractServlet.java:71)

I got Blank page after logging into Webtop 5 for both admin and user. But only when i tried to install 3rd party SSL. Just by simply uploading SSL into Nethserver from GUI never worked. I needed to manually change the SSLCertificateChainFile entry in /etc/httpd/conf.d/ssl.conf.
As soon as SSL started working i no longer got blank page.

Same here. Install of webtop5, SSL cert from letsencrypt (browser says connection is OK).
But nothing to see…
(Should I do stuff as admin for webtop to work properly?)

Please, see /var/log/webtop/webtop.log and share your findings.