# Problem in opening Smart client solution.

**URL:** <https://forum.servoy.com/t/problem-in-opening-smart-client-solution/18340>\
**Category:** Classic Servoy\
**Created:** [February 2, 2015, 6:33am UTC](https://forum.servoy.com/t/problem-in-opening-smart-client-solution/18340 "2015-02-02T06:33:07Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ashutoslenka426](https://avatars.discourse-cdn.com/v4/letter/a/cc9497/32.png) [@ashutoslenka426](https://forum.servoy.com/u/ashutoslenka426)\
**Post date:** [February 2, 2015, 6:33am UTC](https://forum.servoy.com/t/problem-in-opening-smart-client-solution/18340/1 "2015-02-02T06:33:07Z")

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Hi All,

When I am trying to open my smart client solution . It is throwing some exception and not opening . This is a random issue . It is not happening all the time . Please find the exception in the console log :

```auto
java.rmi.UnmarshalException: Error unmarshaling return; nested exception is: 
	java.lang.ClassNotFoundException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException (no security manager: RMI class loader disabled)
	at sun.rmi.transport.StreamRemoteCall.executeCall(Unknown Source)
	at sun.rmi.server.UnicastRef.invoke(Unknown Source)
	at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(Unknown Source)
	at java.rmi.server.RemoteObjectInvocationHandler.invoke(Unknown Source)
	at com.sun.proxy.$Proxy0.getActiveRootObjectsLastModified(Unknown Source)
	at com.servoy.j2db.server.shared.RemoteActiveSolutionHandler.loadLoginSolutionAndModules(RemoteActiveSolutionHandler.java:114)
	at com.servoy.j2db.FlattenedSolution.setSolution(FlattenedSolution.java:590)
	at com.servoy.j2db.ClientState.loadSolutionsAndModules(ClientState.java:1426)
	at com.servoy.j2db.smart.J2DBClient.loadSolutionsAndModules(J2DBClient.java:1948)
	at com.servoy.j2db.smart.J2DBClient$16.run(J2DBClient.java:1907)
	at java.awt.event.InvocationEvent.dispatch(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$200(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

```

Please provide some suggestions on this .

---

<div class="post-metadata">

**Author:** ![jcompagner](https://yyz2.discourse-cdn.com/flex010/user_avatar/forum.servoy.com/jcompagner/32/4889_2.png) [@jcompagner](https://forum.servoy.com/u/jcompagner)\
**Post date:** [May 21, 2015, 8:15am UTC](https://forum.servoy.com/t/problem-in-opening-smart-client-solution/18340/2 "2015-05-21T08:15:10Z")

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you need to check the server, some thing goes wrong with the connection to the database.