Had similar problem when our system administrator renamed the production db server (win 2003) without telling me (the DBA).

Check out BOL:

sp_dropserver

sp_addserver

Although SqlServer (2000) continues running quite happily -...

Don't do it!!!.

Don't make any changes to a production database UNTIL you (and others)have throughly tested the impact.

Hardware config & network changes especially need carefull support from sys admin and...

The obvious answer to this is 'RTFM' (Read The Manual).

BOL = 'Books on Line' also known as 'Help' (click the little button at top right of any Windows screen -...

I got the answer correct - but strictly speaking the explanation should be not that "...the existing rows are 'populated' with NULL..." BUT rather that "...new colums on existing rows...