If you need to enable xp_cmd_shell for someone who is not the sysadmin on your SQL Server following is required:
1. run this transact sql commands:
EXEC sp_configure ‘show advanced options’, 1
GO
RECONFIGURE
GO
EXEC sp_configure ‘xp_cmdshell’, 1
GO
RECONFIGURE
GO
2. for non sysadmin accounts run this transact sql command with proxy account that has sysadmin rights:
EXEC sp_xp_cmdshell_proxy_account ‘LOGIN’, ‘PASSWORD’
Thats it 🙂