how to change server name in sql server

-- If you find any mismatch, then you need to follow below steps:

-- 1. Execute below to drop the current server name

	EXEC sp_DROPSERVER 'oldservername'
    
-- 2. Execute below to add a new server name. Make sure local is specified.

	EXEC sp_ADDSERVER 'newservername', 'local'

-- 3. Restart SQL Services.

-- 4. Verify the new name using:

	SELECT @@SERVERNAME
	SELECT * FROM sys.servers WHERE server_id = 0
    
-- I must point out that you should not perform rename if you are using:

	-- 1. SQL Server is clustered.
	-- 2. Using replication.
	-- 3. Reporting Service is installed.