At run time, you decide the "bitness" of Integration Services package execution on a 64-bit computer by running the 32-bit or the 64-bit version of the dtexec.exe command prompt utility.
At design time in Business Intelligence Development Studio, you can also specify the "bitness" for running the package from within BIDS. The default setting is 64-bit execution. (This setting is ignored on a 32-bit computer, or if you've only installed 32-bit SQL Server on a 64-bit computer.) But on a 64-bit computer, ... [More]