# renaming a sql server with installed named instances

We have a hosted server that is named, by the hosting company, as something like WinEnt99. We would like to rename it to something more meaning like OurMonitor1.

We have already installed a few instances of SQL Server 2008 R2.

Is there anything that we need to (re)configure in SQL Server / SSMS ?

I have an application that was reading the database settings from the registry, and connecting the database fine. Now, it won't connect to the database. The only thing that I can think of is that we renamed the server last week sometime.

EDIT 02 Oct 2012:- The Server is being renamed. The named instances are not.

I've run

sp_helpserver
select @@servername


Which showed the old server name, and

sp_dropserver 'Old Server Name\Instance_name'
go
go


Then confirmed the details in

sp_helpserver
select @@servername

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Did you rename the server and/or the instance name? So in other words, say you had OldServerName\OldInstanceName. Is it now NewServerName\OldInstanceName or NewServerName\NewInstanceName? It isn't clear to me what was changed. –  Thomas Stringer Oct 1 '12 at 16:16
This was cross-posted on SO stackoverflow.com/questions/12676627/… –  bluefeet Oct 2 '12 at 10:09
Which registry settings is the software using to connect to the database? You said you verified the settings used in the CONNECT string - can you manually use this connection string with, say, Microsoft Excel to connect to the database? Does SELECT name FROM sys.servers WHERE server_id=0; show the current name of the server? Is this the name reflected in the registry settings your app is using to build the connect string? More detail can never hurt your situation! –  Max Vernon Oct 2 '12 at 15:50

You are only allowed to change the server name or hostname of a server running SQL server. Microsoft does not support renaming the instance without a reinstall. So if you have a default instance on the server that is referenced by the hostname you can rename the "instance" in that manner. However if you are wanting to go from "hostname\instance1" to "hostname\instance2" you will have to reinstall SQL Server.

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I wasn't clear in my original post. It's the Server that I am renaming, not the Instance name. I have, hopefully, clarified that point. Thank you for your attention. –  cometbill Oct 2 '12 at 11:23

Check the application connection string to see if it references the old name of database instance. For example if your connection string is like:

SERVER=MACHINE\WinEnt99


You would need to change it to:

SERVER=MACHINE\OurMonitor1


If this is not the case, please add more detail to your question, such as the specific error message the application is returning, etc.

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The connection string is built up dynamically using registry settings. I have checked this. Thanks for your time. –  cometbill Oct 2 '12 at 11:23