Total Access Emailer 2010 includes two programs in one to support the 32 and 64 bit editions of Microsoft Access 2010. Microsoft Office 2010 does not allow both the 32-bit and 64-bit editions of Office/Access 2010 to be installed on the same machine.
When you install Total Access Emailer 2010 on your machine, both the 32-bit and 64-bit runtime installers and library references are copied to the Total Access Emailer installation folder.
Remember, this is determined by the bitness of Access 2010, and not the bitness of Microsoft Windows. Even if you are running a 64-bit edition of Windows, if the 32-bit edition of Microsoft Access 2010 is installed, you can only use the 32-bit edition of Total Access Emailer 2010.
You cannot make a library reference to the 64-bit version of Total Access Emailer from the 32-bit version of Access. That means you need to create separate copies of your database to support 32 vs. 64 bit versions of Access, build them with separate installations of Access 2010, and deploy them accordingly.