Unable to open a secure pdf on usb & iPhone

I've updated the latest adobe and updates on my Mac, and managed to open a secure pdf by downloading it as a linked file. However the file doesn't save properly on my usb (that I've tried using at a cafe as I don't have a printer at home). When I opened the doc there's an error message that says I might need the latest version or configuration which I tried to do but got no success. I then tried to print the doc differently through sharing via iCloud or email to my iphone and that also didn't work even with the adobe mobile app. Please help