The update to Android 4.4.2 KitKat didn't just bring good surprises to users of Galaxy Note 3. Now you can not save to the external microSD card with the new update. The problem seems to occur only with certain applications, anyway here is a tutorial to fix it.
Write to SD card on Android 4.4.2 KitKat
Write to SD card on Android 4.4.2 KitKat


