I am a Yahoo member and was logged in, but the files tab is dimmed and unavailable. I have tried logging out and back in again, used different browsers and it still is unavailable. I can access the conversations tab but not the files tab nor the photos tab. When I move over the photos and files tabs a red circle with line through it appears and the tabs won't open.I'm not who you're talking to, but it's in the files section of the ProMaster group. You have to be a member and logged in to Yahoo.
I downloaded it to MyDrive to be able to access it without going into Yahoo