Identity_Insert won't turn off

I'm attempting to append data from an Access table to an SQL 2005 linked
table in Access (ODBC) that has an identity field. So I found that you can
run the following command in SQL Server Management Studio Express (SMSE) to
allow inserts to tables with an identity column:

SET IDENTITY_INSERT [dbo].[TableName] ON

When I run this query in SQL SMSE it works fine, then I run my append query
in Access and it works fine and then I run the following in SQL SMSE:

SET IDENTITY_INSERT [dbo].[TableName] OFF

and it works fine....or so it seems (no error). BUT when I try to run the
ON command again for another table it says its still on for the previous
table. Any ideas why it isn't actually turning it off, even thought the
command completes successfully?

Thanks,
..


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