Paypal - Payflow Pro Modification

We are in the process of upgrading our infrastructure from 32-bit Windows 2003 (IIS 6.0) to 64-bit Windows 2003 (IIS 6.0).? ? We have an .asp application that? serves as our client management system.? ? ? One aspect of the app is credit card processing.? On the 32-bit server, this credit card application ran fine through an older version of Payflow Pro.? In migrating to 64-bit, we were told that we must use the .NET SDK -? <[login to view URL]>? . We will provide the old code and any associated support files to make the transition.