COM object with CLSID ... is either not valid or not registered - packaging (.msi) issue

Question

I created a .msi and installed my app on my test machine ( vmware ).  However, when I try to run the application I get an error ( System.Runtime.InteropServices.COMException( 0x80040154): COM object with CLSID ... is either not valid or not registered.
I created a simple application that has 1 form.  I added the Acrobat .dll as a reference so that I may view pdf's on the form.  It works fine in the IDE but when I try to install on another machine, I'm getting an error.  I thought about trying to register interop.acrobat.dll but that doesn't seem to be the solution.

Any help???

Thanks!!