I had this “The ‘Microsoft.VisualStudio.Editor.Implementation.EditorPackage’ package did not load correctly.” error message when I started up Visual Studio 2013.  My PC had rebooted earlier in the day as a result of some Windows Updates.  Now I was getting this error dialog:

The 'Microsoft.VisualStudio.Editor.Implementation.EditorPackage' package did not load correctly.

This is telling me to open ActivityLog.xml, and hopefully an answer will be found.  So I opened up that file and found some error entries

 <time>2014/02/16 02:00:07.011</time>
 <description>SetSite failed for package [Microsoft.VisualStudio.Editor.Implementation.EditorPackage]</description>
 <hr>80070057 - E_INVALIDARG</hr>
 <errorinfo>No EditorOptionDefinition export found for the given option name: Graphics/Simple/Enable
Parameter name: optionId</errorinfo>

Something must have changed with the Windows updates and it was enough to cause an issue. This problem seems happens enough with various versions of Visual Studio that you can bingle it and get the same answer.  You need to clear the ComponentModelCache folder.  For Visual Studio 2013, it’s located in the %LOCALAPPDATA%\Microsoft\VisualStudio\12.0 folder.

I renamed ComponentModelCache to ComponentModelCache.Borked and restarted Visual Studio.  It started right up and without any errors.