to summarize : I have two disks one with Windows 7, an other with Windows 10. When installed inside my Laptop (at different times) both are booting and running perfectly well. With one installed in the laptop and the other in an USB enclosure connected to the USB 3 port, after having installed Easybcd multiboot, I cannot boot from the drive connected to the USB port. I have the message "Windows could not start a recent modification ...". I can only boot from the disk inside the laptop. After Windows has started, I have full access to both disks.