Problem: mid2011 iMac Mavericks was operating perfectly. Logged off, powered down. Next morning, powered up; system boots normally to login screen. No response to keyboard or trackpad...trackpad light blinks trying to link but will not.
Attempted: Tried usb keyboard no change. Tried all usb ports no change. Plugged keyboard into macbook...works normally; wireless keyboard and trackpad too. Removed batteries from kybd and trackpad; powered up iMac with nothing plugged into ANY port. System boots to login screen but does NOT prompt "No Keyboard or Mouse Found" as it should. HELP!