Hi Mario,
CREATE OBJECT go_excel 'EXCEL.APPLICATION' .
SET PROPERTY OF go_excel 'Visible' = 1 .
GET PROPERTY OF go_excel 'Workbooks' = gs_wbooks .
GET PROPERTY OF go_wbooks 'Application' = go_app .
CALL METHOD OF go_app 'Run'
EXPORTING #1 = macro_string .
Regards