IntelliJ won't start

Delete IDE caches folder: https://intellij-support.jetbrains.com/hc/articles/206544519.

I got a bit further...  Now I see this.  Restarting does not help.  I removed all plugins, caches, etc, then I reinstalled the app..  No luck.

Plugin 'org.jetbrains.kotlin' failed to initialize and will be disabled. Please restart IntelliJ IDEA.

java.lang.ClassNotFoundException: org.jetbrains.kotlin.idea.PluginStartupComponent PluginClassLoader[org.jetbrains.kotlin, 1.0.1-release-IJ143-46]
at com.intellij.ide.plugins.cl.PluginClassLoader.loadClass(PluginClassLoader.java:64)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at com.intellij.openapi.components.impl.ComponentManagerImpl.a(ComponentManagerImpl.java:412)
at com.intellij.openapi.components.impl.ComponentManagerImpl.init(ComponentManagerImpl.java:96)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:458)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:450)
at com.intellij.idea.IdeaApplication.run(IdeaApplication.java:194)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.idea.MainImpl$1$1$1.run(MainImpl.java:61)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:366)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

And this also.  This was after I deleted everything I could find, restarted my computer, and reinstalled.  Is this some kind of permission issue?

Plugin 'org.intellij.scala' failed to initialize and will be disabled. Please restart IntelliJ IDEA.

java.lang.ClassNotFoundException: org.jetbrains.plugins.scala.util.ScalaToolsFactory PluginClassLoader[org.intellij.scala, 3.0.6]
at com.intellij.ide.plugins.cl.PluginClassLoader.loadClass(PluginClassLoader.java:64)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at com.intellij.openapi.components.impl.ComponentManagerImpl.a(ComponentManagerImpl.java:412)
at com.intellij.openapi.components.impl.ComponentManagerImpl.init(ComponentManagerImpl.java:96)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:458)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:450)
at com.intellij.idea.IdeaApplication.run(IdeaApplication.java:194)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.idea.MainImpl$1$1$1.run(MainImpl.java:61)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:366)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

Scala plug-in is not bundled. Are you sure you have removed config/caches/plugins folders per https://intellij-support.jetbrains.com/hc/articles/206544519?

I have done that.   That error was after I reinstalled the app from scratch and selected some plugins.  If I select no plugins I get this:

Internal error. Please report to http://jb.gg/ide/critical-startup-errors

java.lang.RuntimeException: com.intellij.ide.plugins.PluginManager$StartupAbortedException: Fatal error initializing 'com.intellij.openapi.fileTypes.FileTypeManager'
at com.intellij.idea.IdeaApplication.run(IdeaApplication.java:201)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.idea.MainImpl$1$1$1.run(MainImpl.java:61)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:366)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Caused by: com.intellij.ide.plugins.PluginManager$StartupAbortedException: Fatal error initializing 'com.intellij.openapi.fileTypes.FileTypeManager'
at com.intellij.ide.plugins.PluginManager.handleComponentError(PluginManager.java:254)
at com.intellij.openapi.components.impl.PlatformComponentManagerImpl.handleInitComponentError(PlatformComponentManagerImpl.java:43)
at com.intellij.openapi.components.impl.ComponentManagerImpl$ComponentConfigComponentAdapter.getComponentInstance(ComponentManagerImpl.java:540)
at com.intellij.openapi.components.impl.ComponentManagerImpl.createComponents(ComponentManagerImpl.java:123)
at com.intellij.openapi.application.impl.ApplicationImpl.access$801(ApplicationImpl.java:92)
at com.intellij.openapi.application.impl.ApplicationImpl$12.run(ApplicationImpl.java:500)
at com.intellij.openapi.progress.impl.CoreProgressManager$2.run(CoreProgressManager.java:142)
at com.intellij.openapi.progress.impl.CoreProgressManager.a(CoreProgressManager.java:446)
at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:392)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:54)
at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:127)
at com.intellij.openapi.application.impl.ApplicationImpl.createComponents(ApplicationImpl.java:516)
at com.intellij.openapi.components.impl.ComponentManagerImpl.init(ComponentManagerImpl.java:107)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:458)
at com.intellij.openapi.application.impl.ApplicationImpl.load(ApplicationImpl.java:450)
at com.intellij.idea.IdeaApplication.run(IdeaApplication.java:194)
... 20 more
Caused by: java.nio.file.FileSystemException: /Users/wchristopher/Library/Preferences/IntelliJIdea2016.1/filetypes: Too many open files
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:91)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102)
at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107)
at sun.nio.fs.UnixFileSystemProvider.newDirectoryStream(UnixFileSystemProvider.java:407)
at java.nio.file.Files.newDirectoryStream(Files.java:589)
at com.intellij.configurationStore.SchemeManagerImpl.loadSchemes(SchemeManagerImpl.kt:907)
at com.intellij.openapi.fileTypes.impl.FileTypeManagerImpl.initComponent(FileTypeManagerImpl.java:482)
at com.intellij.openapi.components.impl.ComponentManagerImpl$ComponentConfigComponentAdapter.getComponentInstance(ComponentManagerImpl.java:522)
... 33 more

That file /Users/wchristopher/Library/Preferences/IntelliJIdea2016.1/filetypes that it complains about with "too many open files" does not exist 

The system hits the limit of open files. See https://youtrack.jetbrains.com/issue/IDEA-146571#comment=27-1155982.

Use lsof to trace the process which has open lots of files. You can also try increasing this limit.

lsof lists 7592 files but the limit in /etc/sysctl.conf is 20000.  If I run lsof again while that error dialog is up, I see 8658 open files.  The idea process has 915 open files.  Most of these files seem to be jar files inside /Applications/IntelliJ IDEA.app/Contents

What process has most of the other open files?

Chrome has about 3.5K files.  I think I have a lot of tabs open. 

Does it help if you close Chrome or increase the limit even more? Do you still get the same error?

Quitting chrome does not help - I still get that error.

I feel like this has to have something to do with the fact that I upgraded my computer and restored my files from the old one.  Some system files must be corrupt...

Check with "ulimit -a" the actual limits, maybe the .conf file has no effect.

I think ulimit is per-process and the one in /etc is system-wide.  In any case ulimit -n reports 4096

When IDEA displays the error message, please get the losf output for IDEA process ID and attach the results (lsof -p PID).

Before doing that please remove all the IDE caches and plugins once again and reboot.