MetaVis applications are "upwardly compatible", meaning that a 32 bit application of MetaVis can run with on a 64 bit version of Outlook. Conversely, a 64 bit application of MetaVis cannot be run in conjuction with a 32 bit version of Outlook. In this case, you must either upgrade to the 64 bit version of Outlook or switch the MetaVis Application to the 32 bit version.