Cannot access intranet
Please following these steps to solve this problem :
In order to fix, we need to re-initiate the database upgrade manually by invoke below command line.
"C:\Program Files\Common Files\Microsoft Shared\Web server extensions\12\BIN\psconfig -cmd upgrade -inplace b2b -force"
Then restart the server fix the problem.
I strongly recommend we have a periodic complete server backup.
PS: The SQL database for WSS3 is not SQLEXPRESS but it is MICROSOFT##SSEE (Windows Internal Database).