Problem with opening projects in Idea 2016.3.3 Ultimate

I have just installed the trial version of IDEA 2016.3.3 and found out that the projects are not opened correctly anymore. In fact, the project tree window shows only the project node and External libraries node, and the small wheel to the right of the project name remains visible, but nothing further happens. The modules are visible in the Project dialog, but they are not connected to the project properly as the source shows a lot of errors related to the visibility of the classes and other program components.

The log file shows the following error occurring a lot of times while project loading, maybe this is related to the above behavior?

2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - IntelliJ IDEA 2016.3.3  Build #IU-163.11103.6
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - JDK: 1.8.0_112-release
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - VM: OpenJDK Server VM
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - Vendor: JetBrains s.r.o
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - OS: Windows 7
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - Last Action: ShowLog
2017-01-17 19:31:36,167 [1324757]  ERROR - aemon.impl.PassExecutorService - com/intellij/remote/RemoteSdkConnectionAcceptor
java.lang.NoClassDefFoundError: com/intellij/remote/RemoteSdkConnectionAcceptor
    at com.jetbrains.python.psi.impl.PyBuiltinCache.findSdkForFile(PyBuiltinCache.java:95)
    at com.jetbrains.python.psi.impl.PyBuiltinCache.getInstance(PyBuiltinCache.java:80)
    at com.jetbrains.python.inspections.PyPropertyDefinitionInspection$Visitor.<init>(PyPropertyDefinitionInspection.java:86)
    at com.jetbrains.python.inspections.PyPropertyDefinitionInspection.buildVisitor(PyPropertyDefinitionInspection.java:69)
    at com.intellij.codeInspection.InspectionEngine.createVisitorAndAcceptElements(InspectionEngine.java:60)
    at com.intellij.codeInsight.daemon.impl.LocalInspectionsPass.a(LocalInspectionsPass.java:280)
    at com.intellij.codeInsight.daemon.impl.LocalInspectionsPass.a(LocalInspectionsPass.java:249)
    at com.intellij.concurrency.ApplierCompleter.a(ApplierCompleter.java:123)
    at com.intellij.openapi.application.impl.ApplicationImpl.tryRunReadAction(ApplicationImpl.java:1061)
    at com.intellij.concurrency.ApplierCompleter.a(ApplierCompleter.java:96)
    at com.intellij.openapi.progress.impl.CoreProgressManager.a(CoreProgressManager.java:568)
    at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:519)
    at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:54)
    at com.intellij.concurrency.ApplierCompleter.b(ApplierCompleter.java:106)
    at com.intellij.concurrency.ApplierCompleter.compute(ApplierCompleter.java:91)
    at java.util.concurrent.CountedCompleter.exec(CountedCompleter.java:731)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
Caused by: java.lang.ClassNotFoundException: com.intellij.remote.RemoteSdkConnectionAcceptor PluginClassLoader[PythonCore, 5.0.2.143.121]
    at com.intellij.ide.plugins.cl.PluginClassLoader.loadClass(PluginClassLoader.java:64)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 20 more

Actually, the errors are different, but the root cause is always java.lang.NoClassDefFoundError: com/intellij/remote/RemoteSdkConnectionAcceptor.

Any help is greatly appreciated.