UEFI & USB Problems (Legacy USB Support) - [H]ard|Forum
legacy USB means your O/S loaded is Win XP or W98 You have Win 7 so no boot Legacy means O/S not HW USB 2.0 ports will be O.K. with prior 1.0 1.1 USB 3.0 ports will be O.K. with prior 2.0 1.1 1.0 Legacy USB 3 is same prob - if you are using renessa ......