From SAP Business One 9.1, you are able to add attachments to SAP Business One documents. The attachments management functionality also supports activities like updating attachment folder path in SAP Business One documents, setting default attachment folder per user and uploading attachments to subfolders.
Add or Update the Attachments to SAP Business One Documents
If you want to add an attachment to SAP Business One, just define an attachment folder path in company level for all users under. Click Administration > System Initialization > General Settings > Path tab.
It is pretty similar to update an attachments folder in SAP Business One. Instead of creating a new now, just browse the folders and choose Refresh Paths in Documents
Assigning Default Attachment Folders per User
Just simple click Administration > Setup > General > User Defaults > Path tab.