My application exchanges info between Excel and a non-Office application. It
works fine in Excel 2003 because the ActiveWorkbook.Name it assigns to
ThisApp works when you get to AppActivate.

ThisApp = ActiveWorkbook.Name
.... 'programming sends commands to other app
AppActivate ThisApp 'come back to Excel
.... 'programming in Excel

However the ActiveWorkbook.Name assigned to ThisApp by Excel 2007 does not
work when you get to AppActivate. You get an 'object not found' error. It
does work if the first line is changed to read

ThisApp = ActiveWorkbook.Name & " [Compatibility Mode]"

How can I program to distinguish between the two Excel versions and format
ThisApp to correctly deliver the Excel workbook name to the AppActivate
command? Are there any other modes which I might have to contend with
(append to the Excel 2007 name to make it work)?