I was sold a Macbook a1278 and it only has some weird version of windows 10 on it (Everything is all red and inverted colors and the os seems to be all messed up). I tried doing many different things and I have a USB with mountain lion ready to install but nothing is working. What can I try? It has no mac os x utilities or anything at all. I tried booting up internet recovery and the computer fan just spins and black screen..
Boot into recovery mode and if that doesn't exist wipe the entire disk and then boot using the USB drive. You can wipe the disk by removing it from the macbook if recovery mode doesn't work.