Exchange 2010: Unable to open Exchange Management Console - Initialization Failed - Kerberos Authentication Failed

I've been grappling with this issue on and off for a few years now, previously I found no useful information so a simple server restart would fix the problem. It would only pop up occasionally and generally only on a server that had been running for months.

Now I've found a couple of very useful links to help fix the problem quickly and without a reboot!

To fix the Kerberos issue use the steps which Scott Williamson describes here: http://blogs.technet.com/b/whats_on_scotts_mind_today/archive/2012/12/07/exchange-2010-unable-to-open-exchange-management-console-initialization-failed.aspx

A break down as follows:

Problem:  Exchange Management Console in Exchange 2010 will not open and references a server that is down or has been removed from the environment. 

Error Verbiage: Initialization Failed 

The following error occurred while attempting to connect to the specified Exchange server 'exchange.contoso.com': 

The attempt to connect to http://exchange.contoso.com/powershell using 'Kerberos' authentication failed: Connecting to the remote server failed with the following error message : WinRM cannot process the request. The following error occurred while using Kerberos  authentication: The network path was not found.

Resolutions:

Method 1:

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

Method 2:

1. Close all MMC/EMC Instances before proceeding.
2. Open Powershell or Powershell IDE as the user you run the EMC under and execute the following command:.
3. Remove-ItemProperty -Path HKCU:\Software\Microsoft\ExchangeServer\v14\AdminTools\ -Name NodeStructureSettings
4. Close Powershell

After performing either of the methods above to remove the registry entry you should be able to open the Exchange Management Console and it will discover another Exchange server and connect.

After this is fixed I would then run into a problem because I had clicked on 'Retry' too many times which would cause the system load to overrun and stop processing.

The fix is very simple (Almost too simple!) and is detailed here: http://www.vspbreda.nl/nl/2013/07/exchange-2010-error-solved-the-ws-management-service-cannot-process-the-request-the-system-load-quota-of-1000-requests-per-2-seconds-has-been-exceeded/

But the short version is, simply run IISRESET from an elevated command prompt and you're done!