Error "no security manager: RMI class loader disabled" when connecting to a Runtime

Symptom

When you try to connect to a Runtime from the Designer, the following error is thrown:

java.rmi.UnmarshalException: error unmarshalling return; nested exception is: 
	java.lang.ClassNotFoundException: com.indy.engine.common.IEngineConnection (no security manager: RMI class loader disabled)
	at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
	at com.indy.engine.common.EngineFactory.getEngine(EngineFactory.java:17)
	at com.indy.ui.engine.WatchEngine.connect(WatchEngine.java:347)
	at com.indy.ui.engine.WatchEngine.initEngine(WatchEngine.java:148)
	at com.indy.ui.engine.WatchEngine.run(WatchEngine.java:104)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: com.indy.engine.common.IEngineConnection (no security manager: RMI class loader disabled)
	at sun.rmi.server.LoaderHandler.loadProxyClass(LoaderHandler.java:556)
	at java.rmi.server.RMIClassLoader$2.loadProxyClass(RMIClassLoader.java:646)
	at java.rmi.server.RMIClassLoader.loadProxyClass(RMIClassLoader.java:311)
	at sun.rmi.server.MarshalInputStream.resolveProxyClass(MarshalInputStream.java:265)
	at java.io.ObjectInputStream.readProxyDesc(ObjectInputStream.java:1566)
	at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1518)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1781)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1353)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:373)
	... 6 more

 

Solution

This error is raised because you are trying to connect to a Runtime secured with a user / password from a Designer version prior to S18.3.0.

If you want to connect to this Runtime, upgrade your Designer to S18.3.0 or higher.