Friday night I was at a friends place checking out my portable SeaMonkey & FF browsers I have on a flashdrive. Later on, I went to reboot his W7 pc with the flashdrive in, but it didn't reboot. This happened once before & I'm wanting to know why? I've been on other W7 pc's & it rebooted no problem, why not on his? I'm asking because if it happens again, I'd like to know how to fix it. He did get it taken care of, but I'd still like to know why it happens?