Hi, OK, to make a long story short, I decided to upgrade from a new copy of windows 7 which I purchased, to windows 10 before the free upgrade offer ends. So, I disconnected my primary hard drive (which already had 7 on it), plugged in a new one, installed 7, upgraded to 10, disconnected it again, and reconnected my old drive. Now, whenever I start my computer, I see a flash of a boot selection screen, such as the one you might see if you dual boot 7 and XP, before the traditional Windows 7 flag animation, and it's extremely annoying. I tried rebuilding the boot record with my windows 7 disk, changing the bootup settings from the control panel to turn off the boot menu, and going into msconfig to make sure everything was set the way it's supposed to be, but nothing worked. Does anyone have a solution for this? It only flashes for less than a second, but it's still getting on my nerves, and I haven't noticed any other issues, everything else seems perfectly normal. Thanks!