Windows defender program is a newly introduced feature in the Windows 10. This program is responsible for the scanning and removing of virus and infectious files stored in the computer. But sometimes when you launch the program in your PC, you get Windows defender error 0x80508016. Occurring of the defender error code 0x80508016 is a very critical error and you must fix it as soon as possible. There is not any proper reason for the occurring of this issue. But usually it comes due to the deletion of important system files associated with Windows defender program. You should fix Windows error code 0x80508016 using the manual or automatic error fixing methods. For automatic fixing, you can download and install Advanced System Repair Tool in the computer.