Hi! As said in the title, I bought a surface pro 1 refurbished off of amazon to use for school. It was probably an enterprise device as there are 2 areas that look different (stickers probably there), which is the only thing I can think of as why I can't boot from usb. I was trying to install OSX Yosemite (using a guide made by someone who has done it on a surface pro 1, so that's not the problem), and everytime I tried booting from USB nothing happened. I tried the volume down: power+volume down:volume down combo, the volume down: power+volume down combo, changed the bios settings, booting into advanced recovery from Windows 8.1, everything. I can't wrap my head around what isn't working. I even tried a windows install USB that wouldn't boot either. Please help this is killing me!