After a warm boot in BootIt BM, Image for DOS, BootIt UEFI, or Image for UEFI one or more drive devices may be missing.
This issue can be caused by the devices being disabled or not fully initialized by the BIOS.
Enter the system's BIOS and disable the Fast Boot option. Note that some systems also have separate options for devices (e.g. SATA, USB) to disable, partially initialize or fully initialize when booting. For example, if a USB drive has disappeared, make sure that the BIOS is configured to fully initialize USB devices.