After renaming the server, run the following:

--After renaming the physical server , run the following:
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master.dbo.master.dbo.sp_dropserver 'oldServerName'
GO
master.dbo.sp_addserver 'newServerName', 'local'
GO
--Restart the SQL instance at this point.
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--After restarting, run the following to confirm that the previous was successful. Is should return the new server name.
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SELECT @@SERVERNAME AS 'Server Name'
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