Excel addin
 

I am trying to open an excel addin with the extension .xla. I am running
Office 2007. I get the following error message "Opening the VBA project in
this file requires a component that is not currently installed. This file
will be opened without the VBA project. For more information, search
Microsoft Office Online for "VBA converters"". I can find nothing online
with this search term. Advise??