How to download all Sales order attachments (anything image, pdf, xls whatever) to Application Server throgh ABAP program?

Hi Experts,

I need to download all the attachments (whatever type it is) attached to any sales order and purchase order in the ECC system to application server. I am already able to download them through abap program to the presentation server or desktop. But FM  SO_OBJECT_DOWNLOAD does not work to download to app server. Please help.

Thanks,

JC