I am a computer tech and have been getting a lot of Windows 7 computers in lately with this issue. I do not know if anyone on this board has this issue or if it has been addressed in the past on this forum, but I thought I would share my findings. The issue is when the computer downloads a windows update and has to restart to configure. What happens is that the configuration fails and you get a message stating "reverting configuration", then windows restarts. After restarting, the configuring windows message appears again and fails again hence you get stuck in a never ending loop and windows never boots. There are two solutions provided by M$ that seem to work provided this is actually a software configuration issue cause by windows update. They both require you to boot to safe mode. One option is to restore image for an earlier date and the other is to enter command prompt as admin and run the System File Checker by typing "sfc /scannow". Now here is what I have been seeing a lot of... Apparently if your laptop has a memory card reader built in or attached and you do a windows update that requires a restart you may get stuck in this loop (If you leave the memory card in the slot). I have had a ton of people bring their computers and laptops in with this error and all I had to do is remove the memory card and it boots perfectly without configuration failing. It does not seem to be a boot order configuration error, just some glitch when updating windows. I have not been able to verify if it is a certain update that causes this, or if it happens 100% of the time. I only get the computers with issues. In summary, if you are pulling your hair out trying to make your computer boot, make sure to remove the memory card before tossing it out the window.