You haven't provided anywhere near enough detail or code relevant to solving the problem. For example:
• Are you using early binding, or late binding?
• If early binding, have you set a reference to Excel on the Office 2007 system?
• Are the file paths exactly the same on both systems?
• Does whatever workbook is named via StrWkBkNm exist in the same location on both systems?
In the other thread where you initially asked this, I did say you needed to provide all the relevant code...

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]