If you are unable to see the boot menu, try connecting another wired keyboard (if this still does not work, it could be due to a hard drive failure). Select Mac OS using the keyboard arrow keys and press Enter. Hopefully, you will be presented with a boot menu asking you whether you would like to boot in Mac OS or Windows. Continue to hold the Options/Alt key until the mac has fully booted. Press and hold the Options key (apple) or Alt key (windows) while simultaneously powering on the mac by pressing on the power button. Shutdown the mac by holding the power button for ~10 seconds. Solution to anyone else having the same problem of a bootloop in the Windows partition of a mac bootcamp:Ĭonnect an external wired keyboard (can be apple or other brand - I used an old acer KU-0355) to a working USB port (I tested power to the port using a USB led lamp). More information about causes can be found here: So it appears that the Windows partition / system files required for boot has most likely been corrupted - Apparently it can happen for no obvious reason and without any warning upon reboot.