exec sp_configure 'show advanced options',1

reconfigure

exec sp_configure 'Ad Hoc Distributed Queries',1

reconfigure 

exec sp_configure 'Ad Hoc Distributed Queries',0

reconfigure

exec sp_configure 'show advanced options',0

reconfigure

-- To allow advanced options to be changed.

EXEC sp_configure 'show advanced options', 1

GO

-- To update the currently configured value for advanced options.

RECONFIGURE

GO

-- To enable the feature.

EXEC sp_configure 'xp_cmdshell', 1

GO

-- To update the currently configured value for this feature.

RECONFIGURE

GO