Mail Agent Error

We have a issue with Email functions in PDF Architect.

Window: Window 7 Enterprise 64bit

MS Office 2013.

PDF Architect version 1.2.9

When we click to File and click to Mail, it's show a pop-up error "Mail agent error, try to attach file manually".

Anyone can help us how to resolve this issue. We want to attach file direct from PDF Architect application via mail option, don't want attach manually.