Came across a post on DeveloperFusion today that resonated the same issue we had at work a few days earlier involving JET (no not the band) accessing an Access database in .NET code on Windows x64.
If you find you get a nasty:
The Microsoft.Jet.OLEDB.4.0 provider is not registered on the local machine.
When you run your .NET Application – and I know this – on your x64 box, its because Microsoft does not support JET on 64bit versions of Windows outside of Windows 2003.
So, what to do? Simple, you need to make sure that the assembly is written targeting ‘x86’ rather than ‘Any CPU’ or ‘x64’ in the Configuration Manager, rebuild the assemblies and you should be good to go 🙂