Insert a Windows 10 installation disk or recovery drive into a USB slot on your PC. Press the Enter button again to confirm. Press F10 to save the settings and exit BIOS. Change the Boot Mode setting to select Legacy. Then select the Boot tab shown directly below. Enable the F12 Boot Menu setting if it’s disabled. However, you might need to press the Delete key to enter BIOS on some Acer and Dell PCs. You can enter the BIOS setup on most Acer and Dell PCs by pressing the F2 hotkey just after turning them on. Home › Fix › Laptop & PC › No bootable device found