Outlook startup error (Invalid XML)

"Cannot Start Microsoft Outlook. Invalid XML, the View Cannot be Loaded" Error Message

To fix this error, run the Outlook.exe  /ResetNavPane command:

1. Hold the Windows key and the R key at the same time.
2. The Run command window will open. Copy Outlook.exe  /ResetNavPane into the text field.
3. Click OK to run the command.

Source : wvu.teamdynamix.com