We've just completed a migration from Exchange 2010 to 2013 in a single-server environment (well, there was one of each but now 2010 has been uninstalled).  We're running SCOM 2012 and it's reporting the following:

Alert: Health Set unhealthy

Alert description: The total number of messages rejected due to shadow failure over the last 15 minutes exceeds 10

I don't find a matching event in the server log, so I wonder if this is a false alert in SCOM.

From what I've read (http://msexchangeguru.com/2013/04/22/transport/) the Shadow Redundancy doesn't work in a single-server environment and my guess is that it was enabled during our migration from 2010 to 2013.  Should I run "Set-TransportConfig -ShadowRedundancyEnabled $false" now to avoid these errors?  I'm not seeing Shadow Redundancy in the queue like I was during the migration.

Get-TransportConfig shows ShadowRedundancyEnabled:true and RejectMessageonShadowFailure:false.

It also shows the IP address of the old decommissioned 2010 server for "InternalSMTPServers", maybe that's the problem?

Hi,

If there is no user impact, we can temporary do not change the settings till all the migrations are done.
 
Thanks,

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