Battling with sending email from Crystal with MS Outlook x64

This past Friday we started with Crystal's email function not working on any 64 bit OS box. We are now using Crystal 2008 SP3, which has 64 bit OS working with the 32 bit version of Outlook. Unfortunately, we have a large client running the 64 bit version of MS Office, which means 64 bit Outlook. The result is a pop-up that says

Either there is no default mail client or the current mail client cannot fulfill the messaging

request. Please run Microsoft Outlook and set is as the default mail client.

We have gone through several steps to verify that the registry in not corrupt, and that Outlook is set as the default mail client.

Is it possible for the Crystal 2008 email function to work with Outlook x64, and if so what do we need to do? Our interface uses C# .NET 3.5.