'xp_cmdshell' does not exist?

'xp_cmdshell' does not exist??

?

EXEC sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO

EXECsp_configure 'xp_cmdshell',1
GO
RECONFIGURE
GO

Refer?http://msdn.microsoft.com/en-us/library/ms189631.aspx?formore options.

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