Unable to open Exchange Management Console - Initialization Failed

When see this, no worries.. 
Follow the below steps will clear this off and allow you to access the EMC as normal.

1. Close all MMC/EMC instances before proceeding.
2. Open Registry Editor (regedit) as the user you run the EMC under.
3. Go to
4. HKEY_CURRENT_USER\SOFTWARE\Microsoft\ExchangeServer\v14\AdminTools
5. Look for value NodeStructureSetting.
6. If it is there, back it up and then remove it.