Android update will not install venue 3830

Once every two weeks or so, I get a notification that I have an Android update. I click on the Android update and it starts to install and then stops after about 10 to 12 seconds. Then it says error and shuts down then restarts and everything is normal. I am still running Android 4.3 on my Dell Venue 8 3830. I am guessing it is the Android 4.4 KitKat update. Can anyone help me why it will not install? I have had this tablet for month and a half and this is the third or 4th time I've tried to install the update. Can you help me? Why will it not install? is there some setting that I have to change? Or is it a defect in my tablet?