When creating a new Umango zone index you may experience the error:
...The type serialized in the resources file was not the same type that the .resources file said it contained. Expected 'System.Windows.Forms.ListViewItem' but read 'System.Windows.Forms.ListViewItem+ListViewSubItem'
This is related to a bug in .NET. Please install the latest .NET 4.x update from the Microsoft website and the issue should be resolved.
https://www.microsoft.com/en-us/download/details.aspx?id=53344
If this does not resolve the issue then please contact Umango support.
Link to this article http://umango.com/KB?article=78