Is there a way to change the serial number in SQL server without reinstalling it?

I have a SQL Server Standard installed on a server and used my MSDN subscription to download the installation media and install it while in development and test phase. I would like to know how should I proceed after we purchased the license from Microsoft?

Do I need to reinstall the server with the installation media and serial number I purchased or I have some way to enter it or it is enough to have the documents present?

I doubt that changing the CD Key is a supported operation. It is certainly enough to have proof of license should an auditor come around, regardless of the source of the key that activated the product. However from an admin point of view I wouldn't want to support a sql instance that had developers chainging things in the system. I'd do a reinstall with the right key and reinstall the application, and if this was also the test box do a test again, since there is now no guarantee that everything was documented about the config.

Well you don't mention which version you have but try the following;

• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.1\Setup

or

• HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\80\Registration