I use this command on both express and developer addition
select @@VERSION
Express server result is below
Microsoft SQL Server 2008 R2 (RTM) - 10.50.1617.0 (Intel X86)
Apr 22 2011 11:57:00
Copyright (c) Microsoft Corporation
Express Edition with Advanced Services on Windows NT 5.1 <X86> (Build 2600: Service Pack 3)
and developer result is blow
Microsoft SQL Server 2008 (RTM) - 10.0.1600.22 (Intel X86)
Jul 9 2008 14:43:34 Copyright (c) 1988-2008 Microsoft Corporation Developer Edition on Windows NT 5.1 <X86> (Build 2600: Service Pack 3)
When I try to attach the MDF file from my Express edition to my developer edition, I get this error:
An exception occurred while executing a
transact sql statement or batch the
database 'example' cannot be opened
because it is version 661. This
server supports version 655. A
downgrade path is not supported could
not open new database 'example' create
database is aborted. Microsoft Server,
Error: 948
Best Answer
Since your version of Express is newer than your version of Developer, you will not be able to migrate directly, but you have a few options, in my order of preference: