You can't add/remove the IDENTITY column property using an ALTER TABLE
statement.
When you use EM to perform this task, it does a lot of things behind the
scenes. Suppose you have the following table:

CREATE TABLE T1(col1 int NOT NULL)

with identity column property off

Using EM to set the IDENTITY property to col1, and when you run profiler
you'll see something like:

BEGIN TRANSACTION
SET QUOTED IDENTIFIER ON
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
SET ARITHABORT ON
SET NUMERIC ROUNDABORT OFF
SET CONCAT NULL YIELDS NULL ON
SET ANSI NULLS ON
SET ANSI PADDING ON
SET ANSI WARNINGS ON
COMMIT
BEGIN TRANSACTION
CREATE TABLE dbo.Tmp T1
(
col1 int NOT NULL IDENTITY (1, 1)
) ON [PRIMARY]
GO
SET IDENTITY INSERT dbo.Tmp T1 ON
GO
IF EXISTS(SELECT * FROM dbo.T1)
EXEC('INSERT INTO dbo.Tmp T1 (col1)
SELECT col1 FROM dbo.T1 TABLOCKX')
GO
SET IDENTITY INSERT dbo.Tmp T1 OFF
GO
DROP TABLE dbo.T1
GO
EXECUTE sp rename N'dbo.Tmp T1', N'T1', 'OBJECT'
GO
COMMIT

So use Enterprise Manager to perform this task.

--
-Vishal

"BARBARA FLOYD" <com> wrote in message
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