The problem is likely due to incorrect SAP ArchiveLink settings. You can resolve this by following these steps:
Check Display Settings in OAG1:
Go to Transaction OAG1 in your SAP system.
Look for the "Display Stored Documents" setting.
Make sure the option to open documents using the native application or a browser is selected. This allows the browser's built-in PDF viewer to handle the file instead of forcing a download.
Verify Protocol Settings in OAA3:
Open Transaction OAA3.
Check the protocol settings for PDF documents.
Confirm that the application/pdf MIME type is correctly configured to trigger the browser's native application, which prevents the file from being downloaded.