[xwiki-users] Use file path in office macro

We currently display an attached excel file on a wiki page using the office macro and syntax {{office filterStyles="false" reference="attach:MyFile.xlsx"/}}. Instead we'd like to use the path of an file saved on our server, a working url for this is [[unc:\\serverhostname\folder\folder\MyFile.xlsx]] However, {{office reference=" unc:\\serverhostname\folder\folder\MyFile.xlsx " filterStyles="false"/}} does not work (Failed to view office attachment). The Office Macro documentation states: "The supported resources are URLs (url:) and attachments (attach:)." Is there currently a way to use a file path with the office macro? I tried variants using url: but none of them worked. Thank you. Mario