There is no Microsoft.Jet.OLEDB.4.0 provider for 64 bit Windows editions. If you need to use an Excel Source task or Excel Connection Manager in Integration Services on a 64 bit machine (I’m using Vista Ultimate x64), you will need to set your packages, or your project, not to use the 64 bit runtime. This is done by setting the Run64BitRuntime property to false on the project properties’ Debugging tab.
This article on MSDN provides more information about Integration Services running 64 bit editions of SQL Server and Windows.
Also note that if your source file is Excle 2007, the Excel Connection Manager cannot be used and the OLE DB Connection Manager must be used instead. See the note in the linked MSDN article about the Excel Connection Manager.
Technorati tags: SQL Server 2005