exception when finishing a custom "new file wizard" in a RCP project
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I am working with a custom "new file wizard". when i press the finish button i am expecting the eclipse to add a new file and show it correctly, but instead an exception occurs and i can't open the created file.
but if i use this wizard for a second time, the exception doesn't occur and the file opens correctly. why?

the exception occurs when this line "getContainer().run(true, false, op)" executes.

and it is a part of the exception:

!ENTRY org.eclipse.e4.ui.workbench 4 0 2012-07-28 16:15:01.239
!MESSAGE Unable to create class 'org.eclipse.ui.internal.e4.compatibility.CompatibilityEditor' from bundle '33'
!STACK 0
org.eclipse.e4.core.di.InjectionException: java.lang.IllegalArgumentException: can't find IDfind.ext
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:63)
	at org.eclipse.e4.core.internal.di.InjectorImpl.processAnnotated(InjectorImpl.java:857)
	at org.eclipse.e4.core.internal.di.InjectorImpl.processAnnotated(InjectorImpl.java:837)
	at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:111)
	at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:318)
	at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:240)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:161)
	at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.createFromBundle(ReflectionContributionFactory.java:102)
	at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.doCreate(ReflectionContributionFactory.java:71)
	at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.create(ReflectionContributionFactory.java:53)
	at org.eclipse.e4.ui.workbench.renderers.swt.ContributedPartRenderer.createWidget(ContributedPartRenderer.java:141)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createWidget(PartRenderingEngine.java:889)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:623)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:725)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$2(PartRenderingEngine.java:696)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$7.run(PartRenderingEngine.java:690)
.
.
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thanks