Hoe IDENTITY_INSERT in- en uitschakelen met SQL Server 2008?

Via SQL volgens MSDN

SET IDENTITY_INSERT sometableWithIdentity ON

INSERT INTO sometableWithIdentity 
    (IdentityColumn, col2, col3, ...)
VALUES 
    (AnIdentityValue, col2value, col3value, ...)

SET IDENTITY_INSERT sometableWithIdentity OFF

De volledige foutmelding vertelt je precies wat is er mis...