SQL Server blocked access to procedure sys.xp_cmdshell

Error:

xp_cmdshell 'dir c:\Windows'

/*
Msg 15281, Level 16, State 1, Procedure xp_cmdshell, Line 1 [Batch Start Line 0]
SQL Server blocked access to procedure 'sys.xp_cmdshell' of component 'xp_cmdshell' because this component is turned off as part of the security configuration for this server. A system administrator can enable the use of 'xp_cmdshell' by using sp_configure. For more information about enabling 'xp_cmdshell', search for 'xp_cmdshell' in SQL Server Books Online.
*/

Fix:

-- We need to have this ON because xp_cmdshell is an advanced option.
EXEC sp_configure 'show advanced options', 1
GO

-- To update the currently configured values for sp_configure
RECONFIGURE WITH OVERRIDE
GO

-- Now, enable the feature.
EXEC sp_configure 'xp_cmdshell', 1
GO

-- To update the currently configured values for sp_configure
RECONFIGURE WITH OVERRIDE
GO

Sources:

SQL SERVER – FIX: Msg 15281- SQL Server Blocked Access to Procedure ‘sys.xp_cmdshell’ of Component ‘xp_cmdshell’