Resolve error "Root element is missing" in DOC1 Designer



Tree structure of elements Designer's Navigator pane is not visible. See screenshot.

Upon closing the Designer, error message shown is "Root element is missing" (C:\<Directory>\user.config) "Root element is missing". See screenshot.



This can be caused by a corruption of Designer's user.config file.



UPDATED: July 27, 2017
Follow these steps:
1.Make a note of the folder path mentioned in the error message.
2.Close Doc1 Designer.
3.On Windows Explorer, browse to the Doc1 version folder given in the error message. For example '6.0.1835.0" should be found as per the error message appearing in screenshot. 'AppData' is a hidden directory hence  'Show hidden files, folder and drives' under 'Folder Options' needs to be enabled to see this. The other way to access 'AppData' is to give the correct path in the explorer window. As per the error screenshot, AppData will be accessible if patch C:\Users\gu002ch\AppData is opened via Explorer.
4.Delete the user.config file exists in that folder. It is always recommended to make a back up of this file.
5.Launch Designer and login.