Excel automation without Excel installed [Resolved]

[JeffLo]

My program needs to use ActiveX to call MSExcel to open an Excel file and run a macro. However, the MS office was uninstalled from user's computers because considering cost. After uninstalling, part of the users encounter error as below:
<ActiveX component can't create object.>

The error occurs when program try to run below line:

Set xls_Application = New Excel.application

I have already included the Excel 8.0 Object Library in the installation package. And I checked on the client computer, the Library file - Excel8.old still exists under c:\windows\system32\.

The error still appear even I run the setup again and again.

Pls kindly advise how I can fix it.
Many thanks in advance