If you’re looking to move from GP 9 to 10, MSSQL 2000 is not supported. If you’re not a fan of the big bang approach, then maybe you should consider moving to MSSQL 2000 first, and upgrade to GP 10 later.
Users on MSSQL 7.0 need to be on service pack 4 or later, those on MSSQL 2000 need to be on service pack 3 or later.
View information on preparing to install here http://msdn.microsoft.com/en-us/library/ms143719(SQL.90).aspx. and information on upgrading components here http://msdn.microsoft.com/en-us/library/ms143710(SQL.90).aspx. More useful discussions and help can be found on the SQL server technet community: http://technet.microsoft.com/en-us/sqlserver/bb671048.aspx.

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