Recently purchased a used Surface 3. Factory keyboard stopped working after charging all night. Three resets, multiple removing, reinstalling keyboard and drivers. Tried three different keyboard/mouse combos (Bluetooth and 2.4). External mice all work fine. External keyboards work perfectly on login page, but after login, will 'click' when any button is pressed, but no character appears... UNLESS I press and hold the key for 2 seconds, at which time the tablet 'clicks' again, then the character appears. If I continue to hold the key, the tablet will continue to click and produce another character every 2 seconds. Iobit Driver Booster didn't resolve. Windows Update didn't resolve.