Ok, this is of course is not a perfect scenario, because ideally my dev and test environments should be identical to my live enviroment. But anyhow, I had some troubles with Entity Framework today. After deployment my WCF services just threw exceptions (have I ever mentioned that I don’t like WCF for making everything including debugging so difficult – but that’s a different story). After I attached the debugger I finally saw what was really throwing my exceptions. It was one of my LINQ statements on the EDM, telling me:

The version of SQL Server in use does not support datatype ‘datetime2’.

Funny, I thought. Since I don’t use datetime2. It’s actually just a model imported from a SQL 2005 database to SQL 2008. But since I had generated it again from the SQL 2008 (or was it just an update, I can’t remember) it must have remembered this fact and now maps the datetime differently?

The solution in case anyone has the same problem is to open your EDMX in a file editor (or “open with…” in Visual Studio and select XML Editor). At the top you will find the storage model and it has an attribute ProviderManifestToken. This has should have the value 2008. Change that to 2005, recompile and everything works.

Hope it helps.