I walked into my room one day and my computer was in the middle of downdating from 7 to 10, without ever asking me. I held my breath and unplugged the thing from the wall. Luckily nothing happened and it booted back into 7 and I went in and removed every single notion of any update I could, short of physically opening my HDD and removing the physical sections of the platter. Ended up switching to 10 at 11pm on the night 7 ended support. Eh.