java.lang.NoClassDefFoundError: Could not initialize class org.netbeans.modules.masterfs.filebasedfs.FileBasedFileSystem
   at org.netbeans.modules.masterfs.filebasedfs.FileBasedURLMapper.getFileObjects(FileBasedURLMapper.java:107)
   at org.netbeans.modules.masterfs.MasterURLMapper.getFileObjects(MasterURLMapper.java:65)
   at org.openide.filesystems.URLMapper.findFileObject(URLMapper.java:213)
   at org.openide.filesystems.FileUtil.toFileObject(FileUtil.java:889)
   at org.netbeans.core.startup.preferences.PropertiesStorage.toPropertiesFile(PropertiesStorage.java:329)
   at org.netbeans.core.startup.preferences.PropertiesStorage.outputStream(PropertiesStorage.java:263)
   at org.netbeans.core.startup.preferences.PropertiesStorage.save(PropertiesStorage.java:237)
   at org.netbeans.core.startup.preferences.NbPreferences.flushSpi(NbPreferences.java:244)
   at org.netbeans.core.startup.preferences.NbPreferences$1$1.run(NbPreferences.java:86)
   at org.netbeans.core.startup.preferences.PropertiesStorage$3.run(PropertiesStorage.java:354)
   at org.openide.filesystems.EventControl.runAtomicAction(EventControl.java:127)
   at org.openide.filesystems.FileSystem.runAtomicAction(FileSystem.java:641)
   at org.netbeans.core.startup.preferences.PropertiesStorage.runAtomic(PropertiesStorage.java:352)
   at org.netbeans.core.startup.preferences.NbPreferences$1.run(NbPreferences.java:81)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1423)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)