It sounds like there are remnant objects in active directory from a legacy exchange server that was not fully uninstalled.  If the old server was taken offline without a complete and graceful uninstall, then 2013 will not allow you to continue the installation.  

try seeing these instructions for removing legacy servers:  http://technet.microsoft.com/en-us/library/gg576862(v=exchg.141).aspx

• Proposed as answer by gbillig Monday, July 01, 2013 4:00 PM
• Marked as answer by Simon_WuMicrosoft contingent staff, Moderator Thursday, July 18, 2013 6:19 PM

While running the readiness checks during setup of Exchange 2013 I receive the error: One or more servers in the existing organization are running Exchange 2000 or Exchange Server 2003. This is a clean install into an existing O365 Exchange Online environment. No federation services or hybrid configuration. I am migrating from Exchange Online back to on-premise Exchange.

It sounds like there are remnant objects in active directory from a legacy exchange server that was not fully uninstalled.  If the old server was taken offline without a complete and graceful uninstall, then 2013 will not allow you to continue the installation.  

try seeing these instructions for removing legacy servers:  http://technet.microsoft.com/en-us/library/gg576862(v=exchg.141).aspx

Thanks for the reply. Our organization has never ran Exchange 2000 or 2003. We did have 2010 prior to moving to O365. We since removed Exchange 2010 and decommissioned that server.

Hi,

Accessing the AD via ADSIEDIT tool and see whether there are legacy server objects.

Thanks,

OPen Adsiedit on the new exchange server(under installation) and go to Configuration.

Configuration -> Services -> Microsoft Exchange -> ExchangeOrgName -> Administrative Groups -> First Administrative Group -> Servers

Under server you will see your old exchange 2003 server..delete the server and you are all set.in your case you will see your exchange online server like office365.com etc.

In my case I migrated from ex2003 to 2010 and than I was migrating from 2010 to ex2013...it was double hop migration , I got the message while I was preparing schema on my exc2013 machine.

for any assistance

farooque.faisal@yahoo.com

• Edited by Abdul Farooque 5 hours 35 minutes ago