I have been using windows 7 on my macbook pro for a few months perfectly but now I wanted to test os x 10.9 on it, so I partitioned my hard drive and now windows won't boot anymore. The windows partition shows up in finder, disk utility, and the startup pane in system preferences but holding the option key on startup only shows my mac partitions. If I choose windows from the startup pane and reboot it shows a black screen and says "No bootable device -- insert boot disk and press any key." If I delete the new 10.9 partition I can boot windows fine again but do you know any way other than deleting the 10.9 partition to boot windows? I have already tried blessing the windows partition with terminal.